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| United States Patent Application |
20090253181
|
| Kind Code
|
A1
|
|
Vangbo; Mattias
;   et al.
|
October 8, 2009
|
Universal sample preparation system and use in an integrated analysis
system
Abstract
The invention provides for devices and methods for interfacing microchips
to cartridges and pneumatic manifolds. The cartridges, microchips, and
pneumatic manifolds can be integrated with downstream preparation
devices, such as thermal regulating devices and separation and analysis
devices.
| Inventors: |
Vangbo; Mattias; (Fremont, CA)
; Nielsen; William D.; (San Jose, CA)
; Blaga; Lullu I.; (Fremont, CA)
; Stern; Seth; (Palo Alto, CA)
; Horn; Joanne; (Oakland, CA)
; Nguyen; Michael Van; (San Diego, CA)
; Jovanovich; Stevan B.; (Livermore, CA)
|
| Correspondence Address:
|
WILSON SONSINI GOODRICH & ROSATI
650 PAGE MILL ROAD
PALO ALTO
CA
94304-1050
US
|
| Assignee: |
Microchip Biotechnologies, Inc.
Dublin
CA
|
| Serial No.:
|
321594 |
| Series Code:
|
12
|
| Filed:
|
January 21, 2009 |
| Current U.S. Class: |
435/91.1; 204/453; 204/601; 204/660; 422/400; 422/63; 422/68.1; 435/287.2; 436/177 |
| Class at Publication: |
435/91.1; 204/601; 204/660; 204/453; 422/102; 422/63; 422/68.1; 435/287.2; 436/177 |
| International Class: |
C12P 19/34 20060101 C12P019/34; B01D 17/06 20060101 B01D017/06; B01D 57/02 20060101 B01D057/02; B01L 3/00 20060101 B01L003/00; G01N 33/00 20060101 G01N033/00; C12M 1/00 20060101 C12M001/00; G01N 1/18 20060101 G01N001/18 |
Goverment Interests
STATEMENT AS TO FEDERALLY SPONSORED RESEARCH
[0002]Aspects of this invention were made with government support under
one or more of Project No. W911SR-04-P-0047 awarded by the Department of
Defense and Grant No. 5R01HG003583 awarded by the NIH. The government may
have certain rights in this invention.
Claims
1. A device comprising:a microfluidic microchip comprising at least one
port aperture fluidically connected to at least one microfluidic channel
in the microfluidic microchip, wherein the channel comprises at least one
valve that controls movement of a fluid through the channel; anda
cartridge mated to the microchip and comprising a chamber,wherein said
chamber comprises two chamber apertures that are each aligned with a port
aperture of said microfluidic microchip.
2. (canceled)
3. The device of claim 1, wherein said cartridge is fluidically connected
to another cartridge that is mated to another microchip.
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. The device of claim 1, wherein the fluidic volume of said cartridge is
a 100.times. of the fluidic volume of said microfluidic microchip.
11. (canceled)
12. The device of claim 1, wherein said device further comprises a magnet
for applying a magnetic field to the cartridge or the microfluidic
microchip.
13. The device of claim 1, wherein the valve is pneumatically actuated.
14. The device of claim 1, wherein said cartridge is adapted to be
connected to at least one pressure source for the delivery of said at
least one reagent or said at least one sample.
15. (canceled)
16. (canceled)
17. (canceled)
18. The device of claim 1, wherein the microfluidic microchip comprises a
fluidic layer, an elastomeric layer, and a pneumatic layer.
19. The device of claim 1, wherein said cartridge further comprises at
least one input port,wherein said at least one input port is adapted to
mate with a delivery device,wherein said delivery device is fluidically
connected to the fluidic layer of said microfluidic microchip; andwherein
one of said at least one chamber is a closed reaction chamber fluidically
connected to the fluidic layer of said microfluidic microchip.
20. (canceled)
21. (canceled)
22. The device of claim 1, wherein said cartridge is designed toenrich at
least one component from said sample andcomprises at least one sample
input port,wherein said at least one chamber is a closed reaction chamber
comprising beads, andwherein said beads bind to said at least one
component.
23. The device of claim 1, wherein the cartridge further comprises at
least one reagent reservoir comprising reagents for amplifying a nucleic
acid, wherein the at least one reagent reservoir is fluidically connected
to the chamber through the microchip.
24. The device of claim 23, wherein the cartridge further comprises at
least one bead reservoir comprising beads for binding an amplified
nucleic acid, wherein the at least one bead reservoir is fluidically
connected to the chamber through the microchip.
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. A method for performing biochemical reactions comprising:(a) providing
the device of claim 1, and(b) performing at least one enzymatic reaction
within said chamber.
30. (canceled)
31. (canceled)
32. A method for enriching at least one component from a sample
comprising:(a) mating a delivery device to said input port of the device
of claim 19,(b) treating said sample with at least one reagent to
increase the availability of said at least one component for
enrichment,(c) delivering said at least one component to said at least
one reaction chamber of said cartridge,(d) binding said component to one
or more particles in said at least one closed reaction chamber,(e)
washing said particle bound component to remove waste, and(f) eluting
said particle bound component.
33. (canceled)
34. (canceled)
35. (canceled)
36. (canceled)
37. (canceled)
38. (canceled)
39. (canceled)
40. (canceled)
41. (canceled)
42. (canceled)
43. (canceled)
44. (canceled)
45. A device comprising:(a) a first fluid manipulation module
comprising:(i) a first microfluidic microchip comprising a port aperture
fluidically connected to a microfluidic channel in the microfluidic
microchip,wherein the channel comprises at least one valve that controls
movement of a fluid through the channel; and(ii) a cartridge mated to the
microfluidic microchip and comprising at least one sample input port, at
least one chamber, an exit port,wherein the sample input port is
connected to the port aperture,wherein at least one of said at least one
exit ports is aligned with an exit port aperture of said first
microfluidic microchip, andwherein said at least one chamber is
fluidically connected to the fluidic layer of said first microfluidic
microchip;(b) a reaction channel, wherein said reaction channel is not
contained within said first microchip;(c) a temperature modulator,wherein
said reaction channel is fluidically connected to a port on said
cartridge that is fluidically connected to said exit port and at least a
portion of said reaction channel is in thermal contact with said
temperature modulator; and(d) a magnet for applying a magnetic field to
the microfluidic microchip, the cartridge, or the reaction channel.
46. (canceled)
47. (canceled)
48. (canceled)
49. (canceled)
50. A method comprising:delivering a sample containing a nucleic acid to
the device of claim 45;transporting the nucleic acid and an effective
amount of reagents through the portion of the reaction channel in thermal
contact with the temperature modulator one or more times; andamplifying
the nucleic acid; andanalyzing the amplified nucleic acid.
51. (canceled)
52. (canceled)
53. A device comprising:(a) a first microfluidic microchip comprising a
fluidics layer, an actuation layer, and a pneumatic layer,wherein the
fluidics layer comprises one or more microfluidic channels,wherein at
least one of said one or more microfluidic channels comprises an exit
aperture,(b) a flexible connector fluidically connected to the exit
aperture at a first end of the flexible connector;(c) a capillary
fluidically connected to said flexible connector; and(d) a first
electrode and a second electrode,wherein the first electrode and second
electrode are configured to produce an electric field along a path of the
capillary.
54. (canceled)
55. (canceled)
56. (canceled)
57. (canceled)
58. (canceled)
59. (canceled)
60. (canceled)
61. (canceled)
62. (canceled)
63. (canceled)
64. (canceled)
65. (canceled)
66. A method comprising:providing a composition to a microfluidic
microchip,wherein the microfluidic microchip comprises a fluidics layer,
a elastomeric layer, and a pneumatic layer;delivering the composition to
a flexible connector that is fluidically connected to the microfluidic
microchip;providing a electric field to move the composition into a
capillary; andperforming capillary electrophoresis on the composition to
separate a component based on size or charge.
67. (canceled)
68. (canceled)
69. (canceled)
70. (canceled)
71. (canceled)
72. A device comprising:(a) a separation channel fluidically connected to
a loading channel;(b) a forked electrode comprising at least two
electrodes that are electrically connected to the loading channel and the
separation channel through the loading channel,wherein the fluidic
connection between the separation channel and the loading channel is
located between the electrical connections of the two electrodes to the
loading channel; and(c) a pneumatically actuated valve fluidically
connected to the loading channel.
73. (canceled)
74. (canceled)
75. (canceled)
76. (canceled)
77. (canceled)
78. (canceled)
79. (canceled)
80. (canceled)
81. A device comprising:a first, a second, and a third microfluidic
channel that are joined to form a three-way junction;wherein the first
microfluidic channel is electrically connected to a first electrode of a
forked electrode,wherein the second microfluidic channel is electrically
connected to a second electrode of the forked electrode, andwherein the
first, the second, and the third microfluidic channel are each
fluidically connected to a pneumatically actuated valve.
82. A method for performing capillary electrophoresis comprising:providing
the device of claim 72;providing a separation channel solution to the
separation channel;delivering a composition to the loading channel,
wherein the pneumatically actuated valve is used to control the delivery
of the composition to the loading channel; andapplying an electric field
along the separation channel using the forked electrode;performing
capillary electrophoresis on the composition to separate the component
based on size or charge.
83. (canceled)
84. (canceled)
85. A microfluidic device comprising:(a) a microfluidic microchip
comprising:(1) a first channel comprising a first valve;(2) a second
channel that intersects the first channel on one side of the first
valve;(3) a third channel that intersects the first channel on the other
side of the first valve;wherein at least one of the second or third
channel intersect the first channel at a T-valve or at least one of the
second or third channel comprise a second valve, andwherein the second
and third channel each connect to a port; and(b) a fluid loop that is
removably attached to the ports such that fluid can flow from the first
channel to the fluid loop.
86. A microfluidic device comprising:(a) a microchip comprising one or
more pneumatically actuated valves; and(b) a sample loop, wherein the
sample loop is fluidically connected to the one or more pneumatically
actuated valves through ports in the microfluidic microchip, and wherein
the sample loop has a fixed volume and the sample loop is removable.
87. (canceled)
88. (canceled)
89. (canceled)
90. (canceled)
91. (canceled)
92. A method for delivering a fixed volume of fluid to a microfluidic
device comprising:configuring a device with a sample loop comprising a
desired volume, wherein the sample loop is removable;using one or more
pneumatically actuated valves on a microfluidic device to fill the sample
loop with the fixed volume of the fluid; anddelivering the fluid to the
microfluidic device.
93. (canceled)
94. (canceled)
Description
CROSS-REFERENCE
[0001]This application claims the benefit of U.S. Provisional Application
No. 61/022,722, filed Jan. 22, 2008 and U.S. Provisional Application No.
61/140,602, filed Dec. 23, 2008, which are hereby incorporated by
reference in their entirety.
BACKGROUND OF THE INVENTION
[0003]Sample preparation is a ubiquitous problem in biological analytical
systems. The issue of providing sufficiently purified targets from
diverse raw sample types to reliably perform downstream analytical assays
is pervasive and covers cell biology, genomics, proteomics, metabolomics,
food biology, molecular diagnostics, and many other biological and
medical assays. While many advances in sample preparation have been made
the chief solution has been to develop reagents that are used manually or
in robotic systems that use rectilinear stages or multi-axis arms to
manipulate samples.
[0004]Microfluidics and nanofluidics allow miniaturized sample volumes to
be prepared for analysis. Advantages include the nanoscale consumption of
reagents to reduce operating costs and full automation to eliminate
operator variances. Microfluidic sample preparation can either interface
with existing or future detection methods or be part of a completely
integrated system. In the present application, methods and apparatuses
are disclosed that integrate full volume sample preparation with volumes
over 10 mL with microliter and smaller volumes for sample preparation and
analysis.
[0005]Starting from the sample, the present invention can be applied to
concentrate, and pre-separate components for further processing to detect
and classify organisms in matrices comprising aerosol samples, water,
liquids, blood, s
tools, nasal, buccal and other swabs, bodily fluids,
environmental samples with analysis by ELISA, PCR or other nucleic acid
amplification techniques, single molecule detection, protein arrays, mass
spectroscopy, and other analytical methods well known to one skilled in
the art.
[0006]Microfluidic nucleic acid purification can be performed to prepare
the sample for nucleic acid assays. For DNA analysis, PCR amplification
is one current method. Microarray DNA, RNA and protein analysis also
requires extensive sample preparation before the sample can be applied to
the microarray for reaction and readout.
[0007]Samples can be obtained by a wide variety of substrates and
matrices. The matrix may contain complex mixtures including inhibitory
compounds such as hemes, indigo, humic acids, divalent cations, and
proteins etc that interfere with DNA-based amplification. Aerosols can
contain large amounts of molds, metals, and
soils humic and other acids
that all interfere with PCR amplification--the gold standard.
[0008]Early work showed that as few as three seeded organisms could be
detected from diluted samples of soil extracts followed by PCR
amplification of two 16S ribosomal gene fragments.
Low-melting-temperature agarose has been used to extract DNA from
soil
samples for 16S and 18S rDNA PCR amplification using universal primers.
Spun separation gels in column format can be used, such as Sephadex
columns. Multistep purifications such as organic extractions combined
with Sephadex columns were developed. Bead beating was found to be an
effective way to prepare samples for high numbers of organisms and
grinding in liquid nitrogen to detect low numbers of organisms. While
these methods are effective they were best suited for research laboratory
environments.
[0009]Solid phase extractions to columns, beads, and surfaces can be used
to purify DNA before DNA analysis. Proteinase K followed by a Qiagen QIA
Amp silica-gel membrane columns and IsoCode Stix, an impregnated
membrane-based technology, followed by heating, washing and a brief
centrifugation were compared for B. anthracis Sterne vegetative cells in
buffer, serum, and whole blood and spores in buffer and found to work
well.
[0010]A variety of separations can be performed using the devices and
methods of the invention. For example, the devices and methods of the
invention can be used to perform chromatography, phase-based or
magnetic-based separation, electrophoresis, distillation, extraction, and
filtration. For example, a microfluidic channel or a capillary can be
used for chromatography or electrophoresis. As well, beads, such as
magnetic beads can be used for phase-based separations and magnetic-based
separations. The beads, or any other surfaces described herein, can be
functionalized with binding moieties that exhibit specific or
non-specific binding to a target. The binding can be based on
electrostatics, van der Walls interactions, hydrophobicity,
hydrophilicity, hydrogen bonding, ionic interactions, as well as
partially covalent interactions like those exhibited between gold and
sulfur. In preferred embodiments, the devices and methods of the
invention utilize immunomagnetic separations.
[0011]Immunomagnetic separation (IMS) is a powerful technology that allows
targets to be captured and concentrated in a single step using a
mechanistically simplified format that employs paramagnetic beads and a
magnetic field (see Grodzinski P, Liu R, Yang J, Ward M D. Microfluidic
system integration in sample preparation microchip-sets--a summary. Conf
Proc IEEE Eng Med Biol Soc. 2004; 4:2615-8, Peoples M C, Karnes H T.
Microfluidic immunoaffinity separations for bioanalysis. J Chromatogr B
Analyt Technol Biomed Life Sci. 2007 Aug. 30, and Stevens K A, Jaykus L
A. Bacterial separation and concentration from complex sample matrices: a
review. Crit. Rev Microbiol. 2004; 30(1):7-24.). IMS can be used to
capture, concentrate, and then purify specific target antigens, proteins,
toxins, nucleic acids, cells, and spores. While IMS as originally used
referred to using an antibody, we generalize its usage to include other
specific affinity interactions including lectins, DNA-DNA, DNA-RNA,
biotin-streptavidin, and other affinity interactions that are coupled to
a solid phase. IMS works by binding a specific affinity reagent,
typically an antibody or DNA, to paramagnetic beads which are only
magnetic in the presence of an external magnetic field. The beads can be
added to complex samples such as aerosols, liquids, bodily fluids, or
food. After binding of the target to the affinity reagent (which itself
is bound to the paramagnetic bead) the bead is captured by application of
a magnetic field. Unbound or loosely bound material is removed by washing
with compatible buffers, which purifies the target from other, unwanted
materials in the original sample. Because beads are small (nm to um) and
bind high levels of target, when the beads are concentrated by magnetic
force they typically form bead beds of just nL-uL volumes, thus
concentrating the target at the same time it is purified. The purified
and concentrated targets can be conveniently transported, denatured,
lysed or analyzed while on-bead, or eluted off bead for further sample
preparation, or analysis.
[0012]Immunomagnetic separations are widely used for many applications
including the detection of microorganisms in food, bodily fluids, and
other matrices. Paramagnetic beads can be mixed and manipulated easily,
and are adaptable to microscale and microfluidic applications. This
technology provides an excellent solution to the macroscale-to-microscale
interface: beads are an almost ideal vehicle to purify samples at the
macroscale and then concentrate to the nanoscale (100's of nL) for
introduction into microfluidic or nanofluidic platforms. Immunomagnetic
separations are commonly used as an upstream purification step before
real-time PCR, electrochemiluminescence, and magnetic force
discrimination.
[0013]The ability to move fluids on microchips is a quite important. This
invention describes technologies in sample capture and purification,
micro-separations, micro-valves, -pumps, and -routers, nanofluidic
control, and nano-scale biochemistry. A key component of the technology
is Micro-robotic On-chip Valves (MOVe) technology (an example of which is
shown in FIG. 1) and its application to miniaturize and automate complex
workflows. Collectively the MOVe valves, pumps, and routers and the
instrumentation to operate them can be referred to as a microchip fluid
processing platform.
[0014]The heart of the microchip fluid processing platform technology are
MOVe pumps, valves, and routers that transport, process, and enable
analysis of samples. These novel externally actuated,
pneumatically-driven, on-chip valves, pumps, and routers, originally
developed in the Mathies laboratory at the University of California at
Berkeley (U. C. Berkeley) (Grover, W. H. A. M. Skelley, C. N. Liu, E. T.
Lagally, and R. M. Mathies. 2003. Sensors and Actuators B89:315-323;
Richard A. Mathies et al., United States Patent Application, 20040209354
A1 Oct. 21, 2004; all of which are herein incorporated by reference in
their entirety) can control fluidic flow at manipulate volumes from 20 nL
to 10 .mu.L.
[0015]The MOVe valves and pumps (FIG. 1) can combine two glass
microfluidic layers with a polydimethyl siloxane (PDMS) deformable
membrane layer that opens and closes the valve, and a pneumatic layer to
deform the membrane and actuate the valve. The microfluidic channel
etched in the top glass fluidic wafer is discontinuous and leads to vias
through the "via wafer" and microfluidic channels to a valve seat which
is normally closed (FIG. 1A). When a vacuum is applied to the pneumatic
displacement chamber by conventional-scale vacuum and pressure sources,
the normally closed PDMS membrane lifts from the valve seat to open the
valve (FIG. 1B). The bottom panel of FIG. 1 shows a top view of the valve
a similar scale as the other panels.
[0016]Three microvalves can be used to make a micropump on a microchip to
move fluids from the Input area to the Output area on Microchip A. The
fluids are moved by three or more valves. The valves can be created
actuation of a deformable structure. In some implementations a valve seat
is created and in other embodiments no valve seat may be needed. FIG. 2
shows MOVe devices from top to bottom: valve, router, mixer, bead
capture. Self-priming MOVe pumps (FIG. 2, top) are made by coordinating
the operation of three valves and can create flow in either direction.
Routers are made from three or more MOVe valves (FIG. 2, top middle
panel). Mixing has been a holy grail for microfluidics: MOVe mixers (FIG.
2, bottom middle panel) rapidly mix samples and reagents. MOVe devices
work exquisitely with magnetic beads to pump or trap sets of beads (FIG.
2, bottom panel).
[0017]The normally closed MOVe valves, pumps, and routers are durable,
easily fabricated at low cost, can operate in dense arrays, and have low
dead volumes. Arrays of MOVe valves, pumps, and routers are readily
fabricated on microchips. Significantly, all the MOVe valves, pumps, and
routers on a microchip are created at the same time in a simple
manufacturing process using a single sheet of PDMS membrane--it costs the
same to make 5 MOVe micropumps on a microchip as to create 500. This
innovative technology offers for the first time the ability to create
complex micro- and nanofluidic circuits on microchips.
[0018]Patents and applications which discuss the use and design of
microchips include U.S. Pat. No. 7,312,611, issued on Dec. 25, 2007; U.S.
Pat. No. 6,190,616, issued on Feb. 20, 2001; U.S. Pat. No. 6,423,536,
issued on Jul. 23, 2002; U.S. patent Ser No. 10.633,171 Mar. 22, 2005;
U.S. Pat. No. 6,870,185, issued on Mar. 22, 2005 US Application No. US
2001-0007641, filed on Jan. 25, 2001; US Application US20020110900, filed
on Apr. 18, 2002; US patent application 20070248958, filed Sep. 15, 2005;
US patent application US 20040209354, filed on Dec. 29, 2003; US patent
application US2006/0073484, filed on Dec. 29, 2003; US20050287572, filed
on May 25, 2005; US patent application US20070237686, filed on Mar. 21,
2007; US 20050224352 filed on Nov. 24, 2004; US 20070248958, filed on,
Sep. 15, 2005; US 20080014576, filed on Feb. 2, 2007; and, US application
US20070175756, filed on Jul. 26, 2006; all of which are herein
incorporated by reference in their entirety.
SUMMARY OF THE INVENTION
[0019]In one aspect this invention provides a device comprising: a
microfluidic microchip comprising at least one port aperture fluidically
connected to at least one microfluidic channel in the microfluidic
microchip, wherein the channel comprises at least one valve that controls
movement of a fluid through the channel; and a cartridge mated to the
microchip and comprising a chamber, wherein said chamber comprises two
chamber apertures that are each aligned with a port aperture of said
microfluidic microchip. In one embodiment said cartridge is adapted to
receive at least one sample or one reagent. In another embodiment said
cartridge is fluidically connected to another cartridge that is mated to
another microchip. In another embodiment said cartridge comprises at
least two chambers. In another embodiment at least one of said at least
two chambers is adjacent to a movable magnet. In another embodiment at
least one of said at least two chambers is temperature controlled. In
another embodiment at least one of said at least two chambers comprises a
filter. In another embodiment said at least one chamber comprises a
fluidic volume greater than or equal to 5 .mu.L. In another embodiment
said at least one chamber comprises a fluidic volume greater than or
equal to 10 .mu.L. In another embodiment the fluidic volume of said
cartridge is a 100.times. of the fluidic volume of said microfluidic
microchip. In another embodiment one of said at least one chambers
further comprises a filter. In another embodiment said device further
comprises a magnet for applying a magnetic field to the cartridge or the
microfluidic microchip. In another embodiment the valve is pneumatically
actuated. In another embodiment said cartridge is adapted to be connected
to at least one pressure source for the delivery of said at least one
reagent or said at least one sample. In another embodiment said pressure
source provides a positive or negative pressure to the cartridge. In
another embodiment said at least one pressure source is controlled by a
pneumatic solenoid. In another embodiment said at least one pressure
source is a pneumatic manifold. In another embodiment the microfluidic
microchip comprises a fluidic layer, an elastomeric layer, and a
pneumatic layer. In another embodiment said cartridge further comprises
at least one input port, wherein said at least one input port is adapted
to mate with a delivery device, wherein said delivery device is
fluidically connected to the fluidic layer of said microfluidic
microchip; and wherein one of said at least one chamber is a closed
reaction chamber fluidically connected to the fluidic layer of said
microfluidic microchip. In another embodiment said delivery device is
thermally coupled to a temperature modulator. In another embodiment said
delivery device is a syringe. In another embodiment said cartridge is
designed to enrich at least one component from said sample and comprises
at least one sample input port, wherein said at least one chamber is a
closed reaction chamber comprising beads, and wherein said beads bind to
said at least one component. In another embodiment the cartridge further
comprises at least one reagent reservoir comprising reagents for
amplifying a nucleic acid, wherein the at least one reagent reservoir is
fluidically connected to the chamber through the microchip. In another
embodiment the cartridge further comprises at least one bead reservoir
comprising beads for binding an amplified nucleic acid, wherein the at
least one bead reservoir is fluidically connected to the chamber through
the microchip. In another embodiment said beads are paramagnetic beads or
glass beads. In another embodiment said binding of at least one component
to a bead is reversible. In another embodiment said beads are
paramagnetic beads, and wherein said device further comprises a movable
magnet that can attract said paramagnetic beads to the wall of said
closed reaction chamber. In another embodiment said cartridge is designed
to enrich at least one component from a sample, wherein said at least one
component is DNA, RNA, microRNA, siRNA, protein, lipid, or
polysaccharide.
[0020]In another aspect this invention provides a method for performing
biochemical reactions comprising: (a) providing the device comprising a
microfluidic microchip comprising at least one port aperture fluidically
connected to at least one microfluidic channel in the microfluidic
microchip, wherein the channel comprises at least one valve that controls
movement of a fluid through the channel; and a cartridge mated to the
microchip and comprising a chamber, wherein said chamber comprises two
chamber apertures that are each aligned with a port aperture of said
microfluidic microchip, and (b) performing at least one enzymatic
reaction within said chamber. In one embodiment said at least one
enzymatic reaction comprises ligating, blunting, nick repairing,
denaturing, polymerizing, hydrolyzing, phosphorylation or any combination
thereof. In another embodiment the method further comprises separating a
product of said enzymatic reaction using solid-phase particles.
[0021]In another aspect this invention provides a method for enriching at
least one component from a sample comprising: (a) mating a delivery
device to an input port of a device comprising: a microfluidic microchip
comprising at least one port aperture fluidically connected to at least
one microfluidic channel in the microfluidic microchip, wherein the
channel comprises at least one valve that controls movement of a fluid
through the channel; and a cartridge mated to the microchip and
comprising a chamber, wherein said chamber comprises two chamber
apertures that are each aligned with a port aperture of said microfluidic
microchip wherein said cartridge further comprises at least one input
port, wherein said at least one input port is adapted to mate with a
delivery device, wherein said delivery device is fluidically connected to
the fluidic layer of said microfluidic microchip; and wherein one of said
at least one chamber is a closed reaction chamber fluidically connected
to the fluidic layer of said microfluidic microchip, (b) treating said
sample with at least one reagent to increase the availability of said at
least one component for enrichment, (c) delivering said at least one
component to said at least one reaction chamber of said cartridge, (d)
binding said component to one or more particles in said at least one
closed reaction chamber, (e) washing said particle bound component to
remove waste, and (f) eluting said particle bound component. In one
embodiment said delivering comprises pumping said at least one component
to said at least one reaction chamber through said at least one valve of
the microfluidic microchip. In another embodiment said binding comprises
pumping said particles from a reagent port in the cartridge to said at
least one reaction chamber through said at least one valve of the
microfluidic microchip. In another embodiment said particle is a
paramagnetic bead, a nanoparticle, a resin, or a solid-phase particle. In
another embodiment said at least one component is DNA, RNA, microRNA,
siRNA, protein, lipid, or polysaccharide. In another embodiment step (b)
further comprises thermally modulating said delivery device. In another
embodiment step (b) further comprises delivering a lysis reagent or a
component isolation reagent from a reagent port on said cartridge into
said delivery device to increase the availability of said at least one
component for enrichment. In another embodiment the beads of step (d) are
paramagnetic beads. In another embodiment said washing step (e) comprises
attracting said paramagnetic beads with a movable magnet. In another
embodiment said microfluidic microchip directs the flow of said waste in
a second direction. In another embodiment step (c) comprises using
pneumatically actuated valves in the microfluidic microchip or an
external pressure source to deliver said at least one component to said
at least one closed reaction chamber of said cartridge. In another
embodiment the external pressure source provides a positive or negative
pressure to the microfluidic microchip. In another embodiment said sample
delivery device is a syringe.
[0022]In another aspect this invention provides a device comprising: (a) a
first fluid manipulation module comprising: (i) a first microfluidic
microchip comprising a port aperture fluidically connected to a
microfluidic channel in the microfluidic microchip, wherein the channel
comprises at least one valve that controls movement of a fluid through
the channel; and (ii) a cartridge mated to the microfluidic microchip and
comprising at least one sample input port, at least one chamber, an exit
port, wherein the sample input port is connected to the port aperture,
wherein at least one of said at least one exit ports is aligned with an
exit port aperture of said first microfluidic microchip, and wherein said
at least one chamber is fluidically connected to the fluidic layer of
said first microfluidic microchip; (b) a reaction channel, wherein said
reaction channel is not contained within said first microchip; (c) a
temperature modulator, wherein said reaction channel is fluidically
connected to a port on said cartridge that is fluidically connected to
said exit port and at least a portion of said reaction channel is in
thermal contact with said temperature modulator; and (d) a magnet for
applying a magnetic field to the microfluidic microchip, the cartridge,
or the reaction channel. In one embodiment said magnet is adjacent to
said reaction channel. In another embodiment the device further comprises
a second microfluidic microchip that is fluidically connected to said
first microfluidic microchip through said reaction channel. In another
embodiment said temperature modulator is a Peltier device. In another
embodiment the device further comprises a paramagnetic bead.
[0023]In another aspect this invention provides a method comprising:
delivering a sample containing a nucleic acid to a device comprising: (a)
a first fluid manipulation module comprising: (i) a first microfluidic
microchip comprising a port aperture fluidically connected to a
microfluidic channel in the microfluidic microchip, wherein the channel
comprises at least one valve that controls movement of a fluid through
the channel; and (ii) a cartridge mated to the microfluidic microchip and
comprising at least one sample input port, at least one chamber, an exit
port, wherein the sample input port is connected to the port aperture,
wherein at least one of said at least one exit ports is aligned with an
exit port aperture of said first microfluidic microchip, and wherein said
at least one chamber is fluidically connected to the fluidic layer of
said first microfluidic microchip; (b) a reaction channel, wherein said
reaction channel is not contained within said first microchip; (c) a
temperature modulator, wherein said reaction channel is fluidically
connected to a port on said cartridge that is fluidically connected to
said exit port and at least a portion of said reaction channel is in
thermal contact with said temperature modulator; and (d) a magnet for
applying a magnetic field to the microfluidic microchip, the cartridge,
or the reaction channel; transporting the nucleic acid and an effective
amount of reagents through the portion of the reaction channel in thermal
contact with the temperature modulator one or more times; and amplifying
the nucleic acid; and analyzing the amplified nucleic acid. In one
embodiment the method further comprises using the temperature modulator
to perform thermocycling. In another embodiment said reagents are
reagents for polymerase chain reaction or cycle sequencing.
[0024]In another aspect this invention provides a device comprising: (a) a
first microfluidic microchip comprising a fluidics layer, an actuation
layer, and a pneumatic layer, wherein the fluidics layer comprises one or
more microfluidic channels, wherein at least one of said one or more
microfluidic channels comprises an exit aperture, (b) a flexible
connector fluidically connected to the exit aperture at a first end of
the flexible connector; (c) a capillary fluidically connected to said
flexible connector; and (d) a first electrode and a second electrode,
wherein the first electrode and second electrode are configured to
produce an electric field along a path of the capillary. In one
embodiment the flexible connector is surgical, poly(tetrafluoroethylene)
or silicon tubing. In another embodiment the flexible connector is
elastic tubing. In another embodiment the flexible connector has an outer
diameter of about 1.5 to 3 mm and an inner diameter of about 0.25 to 0.5
mm. In another embodiment the flexible connector is also fluidically
connected to a second microfluidic microchip or the first microfluidic
microchip at a second end of the flexible connector. In another
embodiment the flexible connector is fluidically connected to the exit
aperture by a cannula, an upfit tubing, a microtubing fitting, or an
upchurch tubing adapter. In another embodiment the capillary has an outer
diameter of about 150-500 microns and an inner diameter of about 10-100
microns. In another embodiment the capillary is polyamide or
poly(tetrafluoroethylene) coated. In another embodiment the capillary
comprises a separation gel. In another embodiment the capillary is about
10 to 100 cm long. In another embodiment the first electrode is a forked
electrode. In another embodiment said forked electrode comprises one or
more conductive channels or one or more metallic conductors. In another
embodiment the first electrode and the second electrode produce an
electric field that is about 25 to 500 V/cm.
[0025]In another aspect this invention provides a method comprising:
providing the composition to a microfluidic microchip, wherein the
microfluidic microchip comprises a fluidics layer, a elastomeric layer,
and a pneumatic layer; delivering the composition to a flexible connector
that is fluidically connected to the microfluidic microchip; providing a
electric field to move the composition into a capillary; and performing
capillary electrophoresis on the composition to separate a component
based on size or charge. In one embodiment the electric field is about 25
to 500 V/cm. In another embodiment said composition in said tube is
adjacent to a first and second bolus of gas, wherein said first bolus of
gas is upstream of said composition and said second bolus of gas is
downstream of said composition in said tube. In another embodiment said
first and second boluses of gas isolates said composition from other
compositions. In another embodiment the composition comprises at least
one component that is a nucleic acid, protein, fatty acids, or
polysaccharides. In another embodiment the nucleic acid is microRNA, DNA,
RNA, or siRNA.
[0026]In another aspect this invention provides a device comprising: (a) a
separation channel fluidically connected to a loading channel; (b) a
forked electrode comprising at least two electrodes that are electrically
connected to the loading channel and the separation channel through the
loading channel, wherein the fluidic connection between the separation
channel and the loading channel is located between the electrical
connections of the two electrodes to the loading channel; and (c) a
pneumatically actuated valve fluidically connected to the loading
channel. In one embodiment the device further comprises a cannular
electrode in electrical contact with said forked electrode, wherein the
inner diameter of said cannular electrode is at least about 0.2 mm. In
another embodiment said cannular electrode is configured to reduce
injection of gas into said separation channel. In another embodiment the
separation channel is a capillary, and wherein the capillary is
fluidically connected to the pneumatically actuated valve using a
flexible connection. In another embodiment the separation channel is a
microchannel. In another embodiment the separation channel and
pneumatically actuated valve are integrated on a microfluidic microchip.
In another embodiment the loading channel comprises a loading channel
solution and the separation channel comprises a separation channel
solution, and wherein the sample solution has a lower electrical
conductivity than the separation channel solution. In another embodiment
the at least two electrodes comprise at least two microchannels that are
on one end fluidically connected to the loading channel on either side of
the fluidic connection between the separation channel and the loading
channel and on the other end fluidically connected to a base channel. In
another embodiment each of the at least two electrodes is a metallic
conductors that is electrically connected to a voltage source and the
loading channel.
[0027]In another aspect this invention provides a device comprising: a
first, a second, and a third microfluidic channel that are joined to form
a three-way junction; wherein the first microfluidic channel is
electrically connected to a first electrode of a forked electrode,
wherein the second microfluidic channel is electrically connected to a
second electrode of the forked electrode, and wherein the first, the
second, and the third microfluidic channel are each fluidically connected
to a pneumatically actuated valve.
[0028]In another aspect this invention provides a method for performing
capillary electrophoresis comprising: providing a device comprising: (1)
a separation channel fluidically connected to a loading channel; (2) a
forked electrode comprising at least two electrodes that are electrically
connected to the loading channel and the separation channel through the
loading channel, wherein the fluidic connection between the separation
channel and the loading channel is located between the electrical
connections of the two electrodes to the loading channel; and (3) a
pneumatically actuated valve fluidically connected to the loading
channel; providing a separation channel solution to the separation
channel; delivering a composition to the loading channel, wherein the
pneumatically actuated valve is used to control the delivery of the
composition to the loading channel; and applying an electric field along
the separation channel using the forked electrode; performing capillary
electrophoresis on the composition to separate the component based on
size or charge. In another embodiment the composition has a lower
electrical conductivity than the separation channel solution. In another
embodiment the composition is concentrated by said applying the electric
field.
[0029]In another aspect this invention provides a microfluidic device
comprising: (a) a microfluidic microchip comprising: (1) a first channel
comprising a first valve; (2) a second channel that intersects the first
channel on one side of the first valve; (3) a third channel that
intersects the first channel on the other side of the first valve;
wherein at least one of the second or third channel intersect the first
channel at a T-valve or at least one of the second or third channel
comprise a second valve, and wherein the second and third channel each
connect to a port; and (b) a fluid loop that is removably attached to the
ports such that fluid can flow from the first channel to the fluid loop.
[0030]In another aspect this invention provides a microfluidic device
comprising: (a) a microchip comprising one or more pneumatically actuated
valves; and (b) a sample loop, wherein the sample loop is fluidically
connected to the one or more pneumatically actuated valves through ports
in the microfluidic microchip, and wherein the sample loop has a fixed
volume and the sample loop is removable. In one embodiment said
pneumatically actuated valves are actuated by one or more pneumatic
channels in the microfluidic device. In another embodiment the sample
loop comprises a capillary tube. In another embodiment the sample loop is
fluidically connected to a pass-through microfluidic channel at a first
junction and a second junction, and wherein a pass-through microfluidic
pneumatically actuated valve is positioned in the pass-through
microfluidic channel between the first and second junctions. In another
embodiment at least one junction comprises a T-valve, wherein closure of
the T-valve does not prevent passage of fluid through the pass-through
microfluidic channel. In another embodiment the sample loop is connected
to the pass-through microfluidic channel through first and second
channels, and wherein at least one of the first and the second channel
comprise a sample loop valve.
[0031]In another aspect this invention provides a method for delivering a
fixed volume of fluid to a microfluidic device comprising: configuring a
device with a sample loop comprising a desired volume, wherein the sample
loop is removable; using one or more pneumatically actuated valves on a
microfluidic device to fill the sample loop with the fixed volume of the
fluid; and delivering the fluid to the microfluidic device. In one
embodiment the sample loop and a pass-through microfluidic channel are
fluidically connected at a first junction and a second junction, and
wherein at least one junction comprises a T-valve. In another embodiment
the pass-through microfluidic channel comprises a pass-through
microfluidic valve positioned between the first junction and the second
junction.
[0032]In one aspect, this invention provides a device comprising: (a) a
cartridge; (b) a microfluidic microchip having one or more microfluidic
diaphragm valves, fluidically interfaced with the cartridge; and (c) a
pneumatic manifold interfaced with the microfluidic microchip on a
surface of the microfluidic microchip, wherein the pneumatic manifold
covers all or only a portion of the surface of the microfluidic
microchip. In one embodiment the device further comprises a magnet
configured to generate a magnetic field in a chamber of the microfluidic
microchip. In one embodiment wherein the pneumatic manifold has an
annular space for the magnetic component. In another embodiment the
microfluidic microchip comprises a fluidics layer comprising fluidics
channels, a pneumatics layer comprising pneumatics channels, and an
activation layer sandwiched there between, wherein the cartridge
comprises a chamber with an opening, wherein the opening mates with an
opening in the fluidics layer that connects to a fluidics channel, and
the pneumatic manifold comprises an opening that mates with an opening in
the pneumatics layer of the microfluidic microchip that connects with a
pneumatic channel.
[0033]In another aspect this invention provides a device comprising: (a) a
cartridge; (b) a microfluidic microchip having one or more microfluidic
diaphragm valves and interfaced with the cartridge; (c) a pneumatic
manifold interfaced with the microfluidic microchip on a surface of the
microfluidic microchip; and (d) a temperature controlling block in
thermal contact with the cartridge. In one embodiment the microfluidic
microchip comprises a fluidics layer comprising fluidics channels, a
pneumatics layer comprising pneumatics channels, and an activation layer
sandwiched there between, wherein the cartridge comprises a chamber with
an opening, wherein the opening mates with an opening in the fluidics
layer that connects to a fluidics channel, and the pneumatic manifold
comprises an opening that mates with an opening in the pneumatics layer
of the microfluidic microchip that connects with a pneumatic channel.
[0034]In another aspect this invention provides a device comprising a
microfluidic microchip having one or more microfluidic diaphragm valves
and interfaced with a cartridge; wherein the microfluidic microchip has a
bead rail and a reagent rail.
[0035]In another aspect this invention provides a method for amplifying
mRNA and purifying amplified RNA comprising: (a) providing device
comprising: (i) a cartridge; (ii) a microfluidic microchip having one or
more microfluidic diaphragm valves, fluidically interfaced with the
cartridge; (iii) a pneumatic manifold interfaced with the microfluidic
microchip on a surface of the microfluidic microchip, wherein the
pneumatic manifold covers all or only a portion of the surface of the
microfluidic microchip and (iv) a magnet configured to generate a
magnetic field in a chamber of the microfluidic microchip, wherein the
pneumatic manifold has an annular space for the magnetic component; (b)
supplying a sample containing mRNA and reagents to the cartridge; (c)
mixing the sample and reagents in a well of the microfluidic microchip;
(d) amplifying the mRNA to form amplified RNA; (e) capturing the
amplified RNA using magnetic beads; and (f) positioning the magnet in the
annular space to capture magnetic beads in a reservoir of the
microfluidic microchip.
[0036]In another aspect this invention provides a method for amplifying
mRNA comprising: (a) providing a device comprising: (i) a cartridge; (ii)
a microfluidic microchip having one or more microfluidic diaphragm valves
and interfaced with the cartridge; (iii) a pneumatic manifold interfaced
with the microfluidic microchip on a surface of the microfluidic
microchip; and (iv) a temperature controlling block in thermal contact
with the cartridge; (b) supplying a sample containing mRNA and reagents
to the cartridge; (c) mixing the sample and reagents in a well of the
microfluidic microchip to form a mixture; (d) heating the mixture using
the temperature controlling block; and (e) amplifying the mRNA.
[0037]In another aspect this invention provides a method for amplifying
mRNA and purifying amplified RNA comprising: (a) providing a device
comprising a microfluidic microchip having one or more microfluidic
diaphragm valves and interfaced with a cartridge; wherein the
microfluidic microchip has a bead rail and a reagent rail; (b) supplying
reagents to one or more reagent rail wells; (c) supplying magnetic bead
slurry to a bead rail well; (d) supplying a sample containing mRNA to a
sample well; (e) pumping the sample and the reagents to an output well of
the microfluidic microchip to form a mixture; (f) amplifying the mRNA to
form amplified RNA; (g) pumping the magnetic bead slurry to a
purification well; (h) contacting the magnetic bead slurry with amplified
RNA by pumping the amplified RNA to the purification well; and (i)
purifying the amplified RNA.
[0038]In another aspect this invention provides a method for pumping a
fluid in a microfluidic device comprising: (a) providing a microfluidic
device comprising a pumping valve, a source well, and a mixing well,
wherein the pumping valve, the source well, and the mixing well are
fluidically connected by a channel; (b) pumping the fluid in a first
direction through the channel from the source well to the pumping valve;
and (c) pumping the fluid in a second direction through the channel from
the pumping valve to the mixing well, wherein the second direction is
opposite of the first direction.
[0039]Sample preparation is a challenging area of the bioanalytical
process. In one aspect, a method is disclosed for the preparation of
samples from many different sample types. In another aspect, an apparatus
is disclosed that can prepare samples from many different sample types.
In one embodiment, the apparatus operates a cartridge with microscale
valves that direct fluid flow in a microchip component that can be
fabricated separately or as an integral part of the cartridge. In another
embodiment, the apparatus can move samples into the cartridge using
pressure-driven flow or vacuum modulated by the microvalves on the
cartridge. In another embodiment, the apparatus can manipulate
paramagnetic beads for magnetic separation of components of the sample to
purify desired analytes with fluid flow directed by the microvalves.
[0040]In one embodiment, the apparatus is a universal sample preparation
system that can process biological or chemical samples. Samples can be
loaded in liquid, swabs, swipes, solids, gases, or other matrices into
the cartridge. The apparatus is controlled by electronics which may
include a computer to select the proper reagents and direct the fluids
using the microscale valves to open and close circuitry that is formed by
the cartridge and by the microchip component. The sample can be processed
to extract nucleic acids, including DNA, RNA, microRNAs, proteins,
lipids, polysaccharides, cell walls, small molecules, and all other
biological components of a sample. Similarly the sample can also be
processed to extract or purify chemical components. For example, DNA can
be processed onto microbeads.
[0041]In one embodiment, a sample can be moved into a reaction chamber in
a cartridge comprising one or more chambers, channels, tubing, or
capillaries that may be permanently attached to the cartridge or may be
reversibly joined to the cartridge. Samples may be reproducibly
positioned in the channels, tubing or capillaries using vacuum or
pressure modulated or created by micropumps that may be located on the
cartridge, on the apparatus, on an external device, or other
configurations.
[0042]In one embodiment, for DNA, the processed sample can be amplified by
PCR, rolling circle, branched DNA, EXPAR, LAMP, and other DNA
amplification methods well known to one skilled in the art or analyzed by
mass spectroscopy or single molecule detection methods. RNA may be
processed by Reverse Transcriptase real time-PCR, or samples prepared for
DNA microarrays, or other analytical methods. Real time or end point
analyzes can be performed with the apparatus. For proteins, assays may be
performed in the cartridge including enzymatic assays, sandwich
immunoassays, antibody precipitation, protein digestion, protein and
peptide labeling, and other commonly used protein analysis methods.
Similarly, other cellular components or chemicals can be extracted or
purified using standard methods in the apparatus. Molecular biology
methods are readily adapted to the apparatus. Samples can be completely
analyzed on the apparatus in a single cartridge, moved to a separate
cartridge, or analyzed or further processed in a separate instrument
comprising a capillary electrophoresis system or microchip capillary
electrophoresis; multidimensional gel and capillary electrophoresis; mass
spectroscopy, multidimensional mass spectroscopy with HPLC, ICP, Raman
spectroscopy, particle, nanoparticles, and bead based detection, imaging,
comprising fluorescence, IR, optical, or any other analytical systems
well know to one in the art.
[0043]In one embodiment, the integration of a complete sample-to-answer
instrument incorporating the cartridge to prepare DNA samples from many
inputs and sample types and a microchip-based capillary electrophoresis
device for separation of DNA fragments is used for analysis, such as DNA
sequencing, fragment sizing, and forensics.
INCORPORATION BY REFERENCE
[0044]All publications and patent applications mentioned in this
specification are herein incorporated by reference to the same extent as
if each individual publication or patent application was specifically and
individually indicated to be incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045]The novel features of the invention are set forth with particularity
in the appended claims. A better understanding of the features and
advantages of the present invention will be obtained by reference to the
following detailed description that sets forth illustrative embodiments,
in which the principles of the invention are utilized, and the
accompanying drawings of which:
[0046]FIG. 1 depicts an example of a microscale on-chip valve (MOVe).
[0047]FIG. 2 shows a MOVe microvalve, a microrouter, a MOVe mixer, and
bead capture on microchips.
[0048]FIG. 3 shows a fluidic cartridge with MOVe microvalves.
[0049]FIG. 4 shows a fluidic cartridge with ports to a microfluidic
microchip with microvalves.
[0050]FIG. 5 shows a microfluidic microchip with MOVe valves that controls
flows in a cartridge.
[0051]FIG. 6 shows a cartridge connected to reaction chamber and detector
with downstream MOVe pumps and reagents.
[0052]FIG. 7 shows a temperature control device that can thermal cycle and
incorporates magnetic capture, pinch clamps and the capability of cycling
seven reactions simultaneously.
[0053]FIG. 8 shows a temperature control device that can thermal cycle and
incorporates magnetic capture, pinch clamps and the capability of cycling
seven reactions simultaneously.
[0054]FIG. 9 shows PowerPlex16 STR (Single tandem repeat) amplification
reaction performed in a passive, Teflon (PTFE) based Tube reaction
chamber.
[0055]FIG. 10 shows purification of DNA from 25 uL of blood at 69', 23.5',
10.5', and 4.5'; yield in ng is shown on the bars.
[0056]FIG. 11 shows a schematic of using microvalves to capture beads on a
microchip.
[0057]FIG. 12 shows bead capture from a cartridge on a microchip using a
MOVe microvalve.
[0058]FIG. 13 shows bead capture from a cartridge on a microchip using a
MOVe microvalve.
[0059]FIG. 14 shows a capture and reaction microchip using MOVe
microvalves.
[0060]FIG. 15 shows a capture and reaction microchip using MOVe
microvalves.
[0061]FIG. 16 shows a four cartridge assembly.
[0062]FIG. 17 shows an example of STR reactions on microchips.
[0063]FIG. 18 shows a universal sample preparation workflow to prepare
nucleic acids and toxins.
[0064]FIG. 19 shows purification of samples in a cartridge using
paramagnetic beads.
[0065]FIG. 20 shows an integrated pneumatic manifold to operate the MOVe
microvalves in cartridge.
[0066]FIG. 21 shows a cartridge mounted on a computer controlled
apparatus.
[0067]FIG. 22 shows a cartridge mounted on a computer controlled
apparatus.
[0068]FIG. 23 shows a reagent distribution manifold based on MOVe
technology that can distribute five reagents to five extraction/isolation
or other devices.
[0069]FIG. 24 shows a reagent distribution manifold based on MOVe
technology that can distribute five reagents to five extraction/isolation
or other devices.
[0070]FIG. 25 shows a distribution manifold with sample loops and MOVe
microvalves.
[0071]FIG. 26 shows a pneumatic manifold, top panel shows the top side and
the lower panel the bottom side.
[0072]FIG. 27 shows detection of E. coli by immunomagnetic separation,
followed by alkaline lysis and PEG-facilitated capture on magnetic beads,
and analyzed by real-time PCR.
[0073]FIG. 28 shows application of a cartridge with three chambers that
can be used to construct genomic libraries and other applications.
[0074]FIG. 29 shows the workflow to prepare genomic libraries using the
cartridge.
[0075]FIG. 30 shows a forked injector for microchip based electrophoresis.
[0076]FIG. 31 shows sample stacking with a forked injector.
[0077]FIG. 32 shows a forked injector coupled to MOVe microvalves.
[0078]FIG. 33 shows a forked cathode injector coupled with a MOVe
microchip.
[0079]FIG. 34 shows a photograph of a microchip with the forked injector.
[0080]FIG. 35 shows a photograph of a microchip with the forked injector.
[0081]FIG. 36 shows an electropherogram of a single color from a DNA
sequencing trace from a forked cathode injector.
[0082]FIG. 37 shows STR separations on a forked cathode injection system.
[0083]FIG. 38 shows a forked cathode with MOVe microfluidics for shuttle
loading.
[0084]FIG. 39 shows an integrated system for nucleic acid isolation,
amplification(s), separation and detection.
[0085]FIG. 40 depicts a device with a cartridge, microfluidic microchip,
and a magnet.
[0086]FIG. 41 depicts a microfluidic microchip with a fluidics layer, an
elastomeric layer, and a pneumatics layer.
[0087]FIG. 42 depicts a fluidics layer made of two layers of material.
[0088]FIG. 43 depicts a fluidics layer made of a single layer of material.
[0089]FIG. 44 depicts a reaction scheme for amplifying mRNA.
[0090]FIG. 45 depicts an expanded view of a heat block 509, a cartridge
50, a microfluidic microchip 519 and a pneumatics manifold 507.
[0091]FIG. 46 depicts a heat block, a cartridge, a microfluidic microchip
and a pneumatics manifold in an assembled form.
[0092]FIG. 47 depicts fluidics and pneumatic layers of a microfluidic
microchip with four sets of pumps.
[0093]FIG. 48 depicts a cartridge for interfacing with a fluidics layer of
a microfluidic microchip.
[0094]FIG. 49 depicts a block for holding tips that interface with a
cartridge.
[0095]FIG. 50 depicts results of reverse transcription reactions of an
mRNA amplification scheme.
[0096]FIG. 51 depicts an expanded view of a heat block with a heat
distributing element, a cartridge, a microfluidic microchip and a
pneumatics manifold.
[0097]FIG. 52 depicts a heat block with a heat distributing element, a
cartridge, a microfluidic microchip and a pneumatics manifold in an
assembled form.
[0098]FIG. 53 depicts a pneumatics manifold.
[0099]FIG. 54 depicts a pneumatics manifold.
[0100]FIG. 55 depicts a pneumatics manifold.
[0101]FIG. 56 depicts a pneumatics manifold.
[0102]FIG. 57 depicts fluidics and pneumatic layers of a microfluidic
microchip with a reagent and bead rail with the fluidic layer shown in
solid lines and the pneumatics layer shown in dashed lines.
[0103]FIG. 58 depicts fluidics layers of a microfluidic microchip with a
reagent and bead rail.
[0104]FIG. 59 shows a microfluidic microchip with MOVe valves that
controls flows in a cartridge.
[0105]FIG. 60 shows a forked electrode.
[0106]FIG. 61 shows a forked electrode, a forked electrode with a wire run
electrode, and a forked electrode with a cannular electrode.
[0107]FIG. 62 shows sample injection into a separation channel.
[0108]FIG. 63 shows a device for mating a separation capillary with an
injection tubing.
[0109]FIG. 64 shows a device for mating separation capillaries with four
injection tubings.
[0110]FIG. 65 shows a thermocycler with an Ultem pinch clamp.
[0111]FIG. 66 shows a diagram indicating movement of reagents between
components of a four channel parallel processing device.
[0112]FIG. 67 shows a four-channel parallel reagent delivery device: the
Chip C microchip design is shown on the top left, a fluidic manifold is
shown on the bottom left, and the fabricated and assembled device is
shown on the right.
[0113]FIG. 68 shows a four-channel sample preparation device on the left
and a four-channel sample preparation device mounted on a monolithic
pneumatic manifold on the right.
[0114]FIG. 69 shows MOVe microchip designs of the four-channel sample
preparation device: the Chip D microchip design is shown on the left with
flow through valves that form a T-junction between two bisecting channels
shown in top panel; the Chip D microchip design with flow-through valves
is shown on the right top; the Chip F microchip design with in-line
valves that have only one channel passing through the middle of the valve
is shown on the right bottom.
[0115]FIG. 70 shows IdentiFiler STR profiles of DNA samples prepared on
the four-channel sample preparation device, where STR amplifications were
performed using fast protocols (1.5 hrs) on a STR Reaction subsystem
thermocycler.
[0116]FIG. 71 shows a four-channel post amplification device combined with
an Chip A microchip with a fluidics manifold: the Chip A microchip design
is shown on the left, the fabricated microchip is shown in the center,
and the assembled fluidic manifold and microchip is shown on the right.
[0117]FIG. 72 shows a post-amplification STR clean-up subsystem with the
post-amplification device.
[0118]FIG. 73 shows the Chip E microchip design, which can be used a
post-amplification device.
[0119]FIG. 74 shows a diagram of a mixer.
[0120]FIG. 75 shows a diagram of a mixer.
[0121]FIG. 76 shows results of using a mixer to lyse cells.
DETAILED DESCRIPTION OF THE INVENTION
[0122]This invention includes devices that incorporate valves, such as
microvalves (including but not limited to pneumatically actuated valves
and microscale on-chip valves), into their design in order to control the
movement of fluid. These devices can be used for the enrichment of a
component, for sample preparation, and/or for analysis of one or more
components in or from a sample.
[0123]The invention also provides devices for fluid and analyte processing
and methods of use thereof. The devices of the invention can be used to
perform a variety of actions on the fluid and analyte. These actions can
include moving, mixing, separating, heating, cooling, and analyzing. The
devices can include multiple components, such as a cartridge, a
microfluidic microchip, and a pneumatic manifold. FIG. 40 shows an
exemplary device having a cartridge (101), microfluidic microchip (103),
and pneumatic manifold (113).
I. Sample Preparation Device
[0124]In one aspect a sample preparation device as shown in device 800 in
FIG. 16, device 1000 in FIG. 21 and FIG. 22, and device 1000 in FIG. 68
comprises a cartridge integrated with a microfluidic microchip that
controls movement of the fluid in the cartridge through microvalves and
the components to operate the cartridge. The cartridge and/or the
compartments therein can be of sufficient size to process one or more
milliliter of an input sample in an automated device. The cartridge can
process a sample to output a component that can be moved using
pressure-driven flow or vacuum modulated by microvalves. The cartridge
can provide an interface with a delivery device comprising macroscale
samples, such as blood, aerosol liquids, swabs, bodily fluids, swipes,
and other liquid, solid, and gas samples. The cartridge can process
macroscale sample volumes using microscale sample preparation and
analysis. The cartridge can allow for processing of macroscale or large
volume samples using microfluidic devices and components have reduced
void volumes that allow for reduced loss of materials.
A. Cartridges
[0125]A cartridge, also referred to as a fluidic manifold herein, can be
used for a number of purposes. In general, a cartridge can have ports
that are sized to interface with large scale devices as well as
microfluidic devices. Cartridges or fluidic manifolds have been described
in U.S. Patent Application No. 61/022,722, which is hereby incorporated
by reference in its entirety. The cartridge can be used to receive
materials, such as samples, reagents, or solid particles, from a source
and deliver them to the microfluidic microchip. The materials can be
transferred between the cartridge and the microfluidic microchip through
mated openings of the cartridge and the microfluidic microchip. For
example, a pipette can be used to transfer materials to the cartridge,
which in turn, can then deliver the materials to the microfluidic device.
In another embodiment, tubing can transfer the materials to the
cartridge. In another embodiment, a syringe can transfer material to the
cartridge. In addition, a cartridge can have reservoirs with volumes
capable of holding nanoliters, microliters, milliliters, or liters of
fluid. The reservoirs can be used as holding chambers, reaction chambers
(e.g., that comprise reagents for carrying out a reaction), chambers for
providing heating or cooling (e.g., that contain thermal control elements
or that are thermally connected to thermal control devices), or
separation chambers (e.g. paramagnetic bead separations, affinity capture
matrices, and chromatography). Any type of chamber can be used in the
devices described herein, e.g. those described in U.S. Patent Publication
Number 2007/0248958, which is hereby incorporated by reference. A
reservoir can be used to provide heating or cooling by having inlets and
outlets for the movement of temperature controlled fluids in and out of
the cartridge, which then can provide temperature control to the
microfluidic microchip. Alternatively, a reservoir can house Peltier
elements, or any other heating or cooling elements known to those skilled
in the art, that provide a heat sink or heat source. A cartridge
reservoir or chamber can have a volume of at least about 0.1, 0.5, 1, 5,
10, 50, 100, 150, 200, 250, 300, 400, 500, 750, 1000, 2000, 3000, 4000,
5000 or more .mu.L. The relative volume of a chamber or reservoir can be
about 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000 or more
greater than a channel or valve within the microfluidic microchip. The
size of the chambers and reservoirs of the cartridge, which can be mated
to the microfluidic microchip, can be chosen such that a large volume of
sample, such as a sample greater than about 1, 5, 10, 50, 100, 500, 1000,
5000, 10000, 50000 or more .mu.L, can be processed, wherein the flow of
fluids for processing the sample is controlled by valves in the
microfluidic microchip. This can allow for a reduced amount of sample and
reagent loss due to the reduced void volumes in the microfluidic
microchip compared to other flow control devices, such as pipettes and
large scale valves. The void volume within a microfluidic microchip can
be less than 1000, 500, 100, 50, 10, 5, 1, 0.5, 0.1, or 0.05 .mu.L. This
can allow for the amount of sample or reagent loss during processing of a
sample to be less than 20, 15, 10, 7, 5, 3, 2, 1, 0.5, 0.05 percent.
[0126]For example, FIG. 40 shows cartridge (101) with a reservoir with a
port (115) opening to a side of the cartridge that can be used to receive
materials from a pipette or any other large scale device. The port can
also be adapted with fitting to receive tubing or a capillary to connect
the cartridge to upstream fluidics. The reservoir can taper down to form
a cartridge reservoir opening (117) that interfaces, aligns, or mates
with an opening 105 in the fluidics layer of the microfluidic microchip.
[0127]A cartridge can be constructed of any material known to those
skilled in the art. For example, the cartridge can be constructed of a
plastic, glass, or metal. A plastic material may include any plastic
known to those skilled in the art, such as polypropylene, polystyrene,
polyethylene, polyethylene terephthalate, polyester, polyamide,
poly(vinylchloride), polycarbonate, polyurethane, polyvinyldiene
chloride, cyclic olefin copolymer, or any combination thereof. The
cartridge can be formed using any technique known to those skilled in the
art, such as soft-lithography, hard-lithography, milling, embossing,
ablating, drilling, etching, injection molding, or any combination
thereof.
[0128]As exemplified in FIG. 3 and FIG. 4, a cartridge (1) can comprise a
rectilinear configuration with flat sides. In another embodiment, a
cartridge comprises a surface that is curved, rounded, indented or
comprises a protrusion. In one embodiment a cartridge has at least one
substantially flat surface which is adjacent to a microfluidic microchip.
The cartridge is adapted to be fluidically connected with ports in the
microchip. For example, openings in the surface of the cartridge can be
aligned with ports in the microchip. When the cartridge and microchip are
mated to one another, the openings align to create the fluidic
connections allowing liquids to pass from the cartridge into the ports of
the microchip, which are connected to channels typically having valves
that form fluidic circuits. Another embodiment of a cartridge is shown in
FIG. 59. FIG. 59 shows a cartridge with multiple ports that mate with a
microchip and external components, such as syringes. The compartment in
the cartridge can be shaped to allow insertion of the syringe and its
protrusion. The cartridge can also include a vent port to vent gases in
chambers of the cartridge or chambers of the microchip. As well, FIG. 59
shows the position where an actuated magnet can be used to apply a
magnetic field to a mix chamber. Additionally, FIG. 59 shows a cap that
can be used to close the mix chamber.
[0129]In one embodiment a cartridge contains one or more features,
including but not limited to a chamber, a port, a channel or a magnet. In
one embodiment, microvalves, such as pneumatically actuated valves are
combined with the microfluidic cartridge. In some embodiments the
microvalves are active mechanical microvalves (such as magnetic,
electrical, or piezoelectric thermal microvalves), non-mechanical
microvalves (such as bistable electromechanical phase change or
rheological microvalves), external microvalves (such as modular or
pneumatic), passive mechanical (such as check microvalves or passive
non-mechanical (such as capillary microvalves) (Oh et al., A review of
microvalves, J. Micromech Microeng. 16 (2006) R13-R39, herein
incorporated by reference in its entirety)).
[0130]In another embodiment, pneumatically actuated valves, such as MOVe
valves modulate the flow of air pressure, vacuum, or fluids in a
microfluidic microchip 2 or multiple microfluidic microchips. MOVe valves
can be microscale on-chip valves, microfluidic on-chip valves or
micro-robotic on-chip valves. In one embodiment the flow of air pressure,
vacuum, or fluids is regulated by one or more variable pressure pumps,
such as solenoid valves or solenoid pumps. In one embodiment, a
microfluidic microchip is a structure that contains microchannels and/or
microtrenches, where a microchannel is a closed structure and a
microtrench is an open structure. In one embodiment a microfluidic
microchip is a planar structure. In a related embodiment a microfluidic
device comprises a microfluidic microchip with microvalves clustered on
one side of a cartridge. In one embodiment (FIG. 3 and FIG. 4) the
cartridge (1) can comprise one or more ports (4, 5, 6, 7, 8, 9) to
external fluids, air, or vacuum. Functions of the ports can be for waste
(4), reagent entry (5), vent (6), sample input (7), product output (8).
The cartridge (1) can contain one or more sample input or reaction
chambers, (7) and (3).
[0131]A single chamber within the cartridge, such as a reaction chamber,
can have one or more, or at least one, two, or three fluidic connections
to a microchip. For example, reaction chamber (3) can have a fluidic
connection to the microchip through connection 120, which is at the base
of the chamber, and another fluidic connection to the microchip through
port (9), which is connected to chamber (3) through a passageway located
at the top of the chamber. The top of chamber (3), port (9), and the
passageway between chamber (3) and port (9) can be closed from the
exterior environment such that fluids in chamber (3) necessarily are
pumped into port (9) when chamber (3) is full and vice versa. Such a
chamber or combination or chamber and port can be referred to as a closed
chamber. The positioning of the fluidic connections need not necessarily
be at the base and top of the chamber, however, fluidic connections at
the base and top positions of the chamber allow for reduced trapping of
gas in the chamber. Alternatively, reaction chamber (3) can be viewed as
a combination of two chambers that are fluidically connected to each
other at a top position, which can be within the cartridge, and, where
each chamber also has an opening at a base location. The openings at the
base locations, also called chamber apertures, can be fluidically
connected to port apertures on the microchip. The two fluidic connections
can allow for fluids to be directed into and out of the chamber through
the microfluidic microchip.
[0132]In another embodiment a device comprises a cartridge comprising at
least one pneumatically actuated valve, such as a MOVe valve, located on
one or more surfaces or structures in a non-linear manner. A cartridge
can comprise one or more pneumatically actuated valves that are located
within the cartridge, in a location other than the base of the cartridge.
[0133]Functional elements of a cartridge can include ports, channels,
chambers, filters, magnets, or vents, chambers can be collectively
referred to as functional elements. In one embodiment, FIG. 4, the
functional elements connect to the microfluidic microchip containing
microvalves at junctions 100, 120, 140, 160, and 230. The functional
elements can connect with tubing or capillaries inserted into the ports,
by a flush connection, or by fittings. In one embodiment a flush
connection can comprise a port of a cartridge aligned directly with an
aperture of a microfluidic microchip. In one embodiment the cartridge and
microfluidic microchip form an integrated module. In another embodiment
the cartridge and microfluidic microchip are two separate pieces which
are attached together, prior to use.
[0134]A cartridge can comprise at least one chamber, a sample input port,
a reagent port, an exit port, a waste port and a magnet. The magnet can
be located adjacent to the chamber, so that the magnet force generated by
the magnet can attract paramagnetic particles in said chamber to a wall
of the chamber. In one embodiment the paramagnetic particles are beads or
cells rendered magnetically responsive (e.g., cells comprising hemoglobin
that are treated with sodium nitrate). The magnet can be an electric
magnet or a permanent magnet, such as a rare earth metal magnet.
[0135]In one embodiment, FIG. 4, connections or ports (4, 5, 6, 7, 8, and
9) lead to channels in the cartridge (14, 15, 16, 17, 18, and 19)
respectively. Ports (4, 5, 6, 7, and 8) show indents to reliably attach a
connector or tubing to the indent, such as the indent shown for
connection (7) (see the difference in diameter of connection (7) with
channel (17)). In one embodiment, the ports or ports can interface with a
variety of connector or tubes, such as the capillaries as described in
U.S. Pat. No. 6,190,616, U.S. Pat. No. 6,423,536, U.S. application Ser.
No. 09/770,412, Jan. 25, 2001, U.S. Application No. 60/402,959 or one or
more microchips with modular microfluidic ports as described in U.S. Pat.
No. 6,870,185 and U.S. application Ser. No. 11/229,065; all of which are
herein incorporated by reference in their entirety. In one embodiment,
the modular microfluidic ports enable microchips or capillaries to be
reversibly joined without dead volumes or leakage.
[0136]In another embodiment chamber (3) is connected to passageway (9) and
to cone (13), leading to junction (120). Chamber (3) can be used for
reactions as may any of the channels. In FIG. 4 the cartridge channels
lead directly to the apertures of ports on the microchip (2). The
channels of the cartridge can interconnect with each other as needed. In
some embodiments, at least one channel in a cartridge does not physically
connect to a microfluidic microchip. In another embodiment at least one
channel in a cartridge is fluidically connected to at least one
microchannel in a microfluidic microchip. The connection may or may not
utilize an aperture on the microfluidic microchip. An aperture can be an
opening or a fitting designed to mate between the microchip and the
cartridge. In some embodiments of the invention, the fitting comprises a
seal such as a gasket or an o-ring.
B. Microchips
[0137]In one embodiment a cartridge and a microfluidic microchip are
integrated together to form a single modular device. The cartridge and a
microfluidic microchip can be attached by a fluid or solid adhesive or
mechanically. In one embodiment the adhesive is a polyacrylate, adhesive
tape, double-sided tape, or any other adhesive known to one skilled in
the art. A cartridge can comprise a feature (12) that is capable of
wicking a fluid-based adhesive into the junction between a microfluidic
microchip and a cartridge. In another embodiment a cartridge is attached
to a microfluidic microchip with a non-fluidic adhesive layer.
Alternatively, the cartridge and microchip can be held together by clips,
clamps, or another holding device. The cartridge and microchip can be
aligned prior to integration by visual cues, with or without a
microscope, or by physical guiding features. Visual cues can include
lines or features that are drawn, etched, or otherwise present on the
cartridge, the microchip, or both. Physical guiding features include
indentations, protrusions, and edges that can be `keyed` to aid or insure
proper assembly.
[0138]In some instances, the microfluidic microchip has diaphragm valves
for the control of fluid flow. Microfluidic devices with diaphragm valves
that control fluid flow have been described in U.S. Pat. No. 7,445,926,
U.S. Patent Publication Nos. 2006/0073484, 2006/0073484, 2007/0248958,
and 2008/0014576, and PCT Publication No. WO 2008/115626, which are
hereby incorporated by reference in their entirety. The valves can be
controlled by applying positive or negative pressure to a pneumatics
layer of the microchip through a pneumatic manifold.
[0139]In one embodiment, the microchip is a "MOVe" microchip. Such
microchips comprise three functional layers--a fluidics layer that
comprises microfluidic channels; a pneumatics layer that comprises
pneumatics channels and an actuation layer sandwiched between the two
other layers. In certain embodiments, the fluidics layer is comprised of
two layers. One layer can comprise grooves that provide the microfluidics
channels, and vias, or holes that pass from the outside surface to a
fluidics channel. A second layer can comprise vias that pass from a
surface that is in contact with the actuation layer to the surface in
contact with the pneumatic channels on the other layer. When contacted
together, these two layers from a single fluidics layer that comprises
internal channels and vias that open out to connect a channel with the
fluidics manifold or in to connect a channel with the activation layer,
to form a valve, chamber or other functional item. The actuation layer
typically is formed of a deformable substance, e.g., an elastomeric
substance, that can deform when vacuum or pressure is exerted on it. At
points where the fluidic channels or pneumatic channels open onto or are
otherwise in contact with the actuation layer, functional devices such as
valves can be formed. Such a valve is depicted in cross section in FIG.
1. Both the fluidics layer and the pneumatics layer can comprise ports
that connect channels to the outside surface as ports. Such ports can be
adapted to engage fluidics manifolds, e.g., cartridges, or pneumatics
manifolds.
[0140]As shown in FIG. 40, the microfluidic microchip (103) can be
interfaced with the cartridge (101). The microfluidic microchip can have
a chamber (105) with an opening that is mated to an opening (117) of the
cartridge (101). The chamber can be used for a variety of purposes. For
example, the chamber can be used as a reaction chamber, a mixing chamber,
or a capture chamber. The chamber can be used to capture magnetic
particles such as magnetic beads, paramagnetic beads, solid phase
extraction material, monoliths, or chromatography matrices.
[0141]A magnetic component (109) can be positioned such that magnetic
particles in the cartridge reservoir (107) and/or the microfluidic
chamber (105) are captured against a surface of the microfluidic chamber
(105). The magnetic component can generate a magnetic and/or
electromagnetic field using a permanent magnet and/or an electromagnet.
If a permanent magnet is used, the magnet can be actuated in one or more
directions to bring the magnet into proximity of the microfluidic
microchip to apply a magnetic field to the microfluidic chamber. In some
embodiments of the invention, the magnet is actuated in the direction
(111) indicated in FIG. 40.
[0142]Alternatively, any of a variety of devices can be interfaced with
the microfluidic microchip. For example detectors, separation devices
(e.g. gas chromatographs, liquid chromatographs, capillary
electrophoresis, mass spectrometers, etc), light sources, or temperature
control devices can be positioned next to the microfluidic microchip or
used in conjunction with the microfluidic microchip. These devices can
allow for detection of analytes by detecting resistance, capacitance,
light absorbance or emission, fluorescence, or temperature or other
chemical or physical measurements. Alternatively, these devices can allow
for light to be introduced to a region or area of the microfluidic
microchip.
[0143]A microfluidic device can be designed with multiple chambers that
are configured for capture of magnetic particles. The multiple chambers
and magnetic component can be arranged such that a magnetic field can be
applied simultaneously to all chambers, or be applied to each or some
chambers independent of other chambers. The arrangement of chambers and
magnetic components can facilitate faster or more efficient recovery of
magnetic particles. In particular, the arrangement can facilitate
recovery of magnetic particles in multiple chambers.
[0144]As shown in FIG. 41, the microfluidic microchip (103) can be formed
of a fluidics layer (203), an elastomeric layer (205), and a pneumatic
layer (207). The fluidics layer can contain features such as a chamber
(105), as well as channels, valves, and ports. The channels can be
microfluidic channels used for the transfer of fluids between chambers
and/or ports. The valves can be any type of valve used in microfluidic
devices. In preferred embodiments of the invention, a valve includes a
microscale on-chip valve (MOVe), also referred to as a microfluidic
diaphragm valve herein. A series of three MOVes can form a MOVe pump. The
MOVes and MOVe pumps can be actuated using pneumatics. Pneumatic sources
can be internal or external to the microfluidic microchip.
[0145]An example of a MOVe valve is shown in FIG. 1. A cross-sectional
view of a closed MOVe valve is shown in FIG. 1A. A cross-sectional view
of an open MOVe valve is shown in FIG. 1B. FIG. 1C shows a top-down view
of the MOVe valve. A channel (251) that originates from a fluidic layer
can interface with an elastomeric layer (259) by one or more vias (257).
The channel can have one or more seats (255) to obstruct flow through the
channel when the elastomeric layer (259) is in contact with the seat
(255). The elastomeric layer can either be normally in contact with the
seat, or normally not in contact with the seat. Application of positive
or negative pressure through a pneumatic line (261) to increase or
decrease the pressure in a pneumatic chamber (253) relative to the
fluidic channel (251) can deform the elastomeric layer, such that the
elastomeric layer is pushed against the seat or pulled away from the
seat. In some embodiments of the invention, a MOVe does not have a seat,
and fluid flow through the fluidic channel is not completely obstructed
under application of positive or negative pressure. The vacuum that can
be applied include extremely high vacuum, medium vacuum, low vacuum,
house vacuum, and pressures such as 5 psi, 10 psi, 15 psi, 25 psi, 30
psi, 40 psi, 45 psi, and 50 psi.
[0146]Three MOVe valves in series can form a pump through the use of a
first MOVe as an inlet valve, a second MOVe as a pumping valve, and a
third MOVe as an outlet valve. Fluid can be moved through the series of
MOVes by sequential opening and closing of the MOVes. For a fluid being
supplied to an inlet valve, an exemplary sequence can include, starting
from a state where all three MOVes are closed, (a) opening the inlet
valve, (b) opening the pumping valve, (c) closing the inlet valve and
opening the outlet valve, (d) closing the pumping valve, and (e) closing
the outlet valve. Since the inlet and outlet valve can have the same
structure, a MOVe pump can move fluids in either direction by
reprogramming of the sequence of opening inlet or outlet valves.
[0147]The fluidic layer (203) can be constructed of one or more layers of
material. As shown in FIG. 42, the fluidic layer (203) can be constructed
of two layers of material. Channels (301, 303, 305) can be formed at the
interface between the two layers of material, and a chamber (105) can be
formed by complete removal of a portion of one layer of material. The
channels can have any shape, e.g., rounded and on one side (301),
rectangular (303), or circular (305). The channel can be formed by
recesses in only one layer (301, 303) or by recesses in both layers
(305). The channels and chambers can be connected by fluidic channels
that traverse the channels and chambers shown. Multidimensional
microchips are also within the scope of the instant invention where
fluidic channels and connections are made between multiple fluidic
layers.
[0148]The thickness (307) of the second layer of material can be of any
thickness. In some embodiments of the invention, the second layer has a
thickness that minimizes reduction of a magnetic field in the chamber
(105) that is applied across the second layer from an external magnetic
component or minimizes reductions in heat transfer.
[0149]As shown in FIG. 43, the fluidic layer (203) can be constructed of a
single layer of material. The single layer is then interfaced with an
elastomeric layer, such that channels (305, 303) and chambers (305) are
formed between the fluidic layer and the elastomeric layer (205).
[0150]The microfluidic microchip can be constructed from any material
known to those skilled in the art. In some embodiments of the invention,
the fluidics and pneumatic layer are constructed from glass and the
elastomeric layer is formed from PDMS. In alternative embodiments, the
elastomer can be replaced by a thin membrane of deformable material such
as Teflon (PTFE), silicon, or other membrane. The features of the
fluidics and pneumatic layer can be formed using any microfabrication
technique known to those skilled in the art, such as patterning, etching,
milling, molding, embossing, screen printing, laser ablation, substrate
deposition, chemical vapor deposition, or any combination thereof.
[0151]In one embodiment, microchannel circuits are formed on a
microfluidic microchip 2, as shown in FIG. 5, linking sets of microvalves
with microchannels. In one embodiment the microvalves are pneumatically
actuated valves. In one embodiment the pneumatically actuated valves are
MOVe microvalves. In one embodiment, the fluidic path between a cartridge
and a microfluidic microchip, such as between chambers, ports, channels,
microchannels, and other functional elements can be controlled by opening
or closing at least one microvalve. In one embodiment the microvalve is
controlled by a microprocessor control such as a computer. A computer can
include an input/output controller, or any other components known to one
skilled in the art such as memory storage and a processor. In one
embodiment, a microvalve is a MOVe valve that is actuated by a pneumatic
source, such as through pneumatic ports 10, 20, 30, 40, 50, 60, or 70. In
one embodiment the pneumatic source is controlled by at least one
solenoid. In one embodiment the solenoid is miniaturized and can be
connected to vacuum or pressure sources. In one embodiment the pneumatic
source is connected to a pneumatic port using a force such as clamping,
springs, pneumatics, or a screw force, optionally with sealing provided
by an o-ring.
[0152]In one embodiment FIG. 5 shows a view of the top of a microfluidic
microchip (2), this side makes contact with the bottom of cartridge (1).
A microvalve 110 controls the fluidic path between microchannels 101 and
121. A microvalve 130 controls the fluidic path between microchannels 131
and 141. Microvalve (150) controls the fluidic path between microchannels
151 and 152. Microvalve 180 controls the fluidic path between
microchannels 181 and 191. Microvalve 200 controls the fluidic path
between microchannels 201 and 212. Microvalve 220 controls the fluidic
path between microchannels 221 and 231.
[0153]In one embodiment junctions can connect one or more microchannels.
FIG. 5 shows the schematic for a microchip that can be mated with the
cartridge shown in FIG. 4. In FIG. 5, junction 100 connects to single
microchannel 101, junction 140 connects to single microchannel 141,
junction 160 connects to single microchannel 161, and junction 230
connects to single microchannel 231. Junction 190 connects to two
microchannels 191 and 201. Junction 120 connects to three microchannels
121, 131, and 151. In one embodiment more than three microchannels can be
connected to a single junction.
[0154]The microchannels can be fabricated by one or more techniques such
as photolithography, molding, embossing, casting, or milling. The
microchannels can be manufactured in a material such as glass, plastic,
polymer, ceramic, gel, metal, or another suitable solid.
[0155]In another embodiment a device comprises a cartridge comprising at
least three chambers, more than one input port and more than one output
port (FIG. 28). The cartridge can be adapted to process a nucleic acid
sample for analysis. The cartridge can be adapted to receive one or more
reagents from an external reagent source. The reagents can be a
paramagnetic bead, a non-paramagnetic bead, an enzyme, a dNTP, a buffer
solution, a salt solution, an alcohol solution, an solution comprising
EDTA or an oligonucleotide or other reagents. The enzymes can be a
ligase, a restriction enzyme, a polymerase, or a kinase or any other
enzyme or catalytic biomaterials including RNAs. The device can comprise
a magnet which can attract paramagnetic beads to a wall of one or more
chambers. In another embodiment at least one chamber comprises a filter
to capture beads, such as non-paramagnetic beads.
[0156]In one embodiment the cartridge is used in a method of sample
enrichment comprising: delivery of a sample to a chamber by a sample port
and delivery of paramagnetic particles to a chamber by a reagent port.
The paramagnetic particles (e.g. paramagnetic beads) bind to at least one
component in the sample (such as DNA, RNA, micro RNA, a protein, a lipid,
a polysaccharide or other ligand). The paramagnetic particles are
attracted to a wall of a chamber by virtue of the magnetic force exerted
by a magnet located outside the chamber. The paramagnetic particles are
washed with a wash solution delivered to the chamber comprising the
paramagnetic particles by a reagent port, and the wash solution is
removed by a waste port. A reagent can be added to elute the component of
the sample from the paramagnetic particles and output the sample
component to another device for further processing or analysis. A
preferred embodiment is to output the component of the sample on the
paramagnetic particles.
[0157]In one embodiment a device comprising a microfluidic microchip is
used in a method of diagnosis. In one embodiment the diagnosis comprises
the detection of an infectious agent in a sample. In one embodiment the
infectious agent is a bacteria, virus, fungi, mycoplasm or prion. In
another embodiment a device comprising a microfluidic microchip is used
in a method of diagnosis of a hereditary disease. In one embodiment the
hereditary disease is caused by one or more DNA mutations, such mutations
include but are not limited, triplet base expansions, base substitution
mutations, deletion mutations, addition mutations, nonsense mutations,
premature stop codons, chromosomal deletions, chromosomal duplications,
aneuploidy, partial aneuploidy or monosomy. In another embodiment a
device comprising a microfluidic microchip is used in a method to
diagnose cancer or a predisposition to cancer. In another embodiment a
device comprising a microfluidic microchip is used in a method to
diagnose a hereditary disease such as autism, downs syndrome, trisomy,
Tay-sachs, or other hereditary diseases. In some embodiments a sample
used for diagnosis in a device comprising a microfluidic microchip is a
blood sample, a mucus sample, a lung lavage sample, a urine sample, a
fecal sample, a skin sample, a hair sample, a semen sample, a vaginal
sample, or an amniotic sample.
[0158]In another embodiment a device comprising a microfluidic microchip
is used to identify the presence of environmental contamination of an
agent. In one embodiment the agent is a biological agent such as
bacteria, virus, fungi, or mycoplasm in an environmental sample. In
another embodiment the agent is a contaminant agent, such as a pesticide,
an herbicide, or a fertilizer. In one embodiment the environmental sample
is a soil sample, a water sample, an air sample, a meat sample, a
vegetable sample or a fruit sample. In another embodiment, the agent is a
genetically modified organism.
[0159]In another embodiment a device comprising a microfluidic microchip
is used for genotyping, identification of an individual mammal (such as a
human), forensics, gene expression, gene modification, microRNA analysis,
or ribotyping.
[0160]In another embodiment a microfluidic microchip is used in a method
comprising molecular biological analysis, including but not limited to
polymerase chain reaction (PCR) amplification of nucleic acids in a
sample (such as Allele-specific PCR, Assembly PCR, Asymmetric PCR, Colony
PCR, Helicase-dependent amplification, Hot-start PCR,
Intersequence-specific (ISSR) PCR, Inverse PCR, Ligation-mediated PCR,
Methylation-specific PCR Multiplex Ligation-dependent Probe
Amplification, Multiplex-PCR, Nested PCR, Overlap-extension PCR,
Quantitative PCR Reverse Transcription PCR-PCR, Thermal asymmetric
interlaced-PCR, Touchdown PCR, or PAN-AC PCR), isothermal nucleic acid
amplifications, (such as Loop-mediated Isothermal Amplification (LAMP);
nick displacement amplification; Helicase Dependant Amplification
platform (HDA); and the primase-based Whole Genome Amplification platform
(pWGA); single primer isothermal amplification (SPIA) and Ribo-SPIA for
RNA; strand displacement amplification (SDA); EXPAR [Van Ness J, Van Ness
L K, Galas D J. (2003) Isothermal reactions for the amplification of
oligonucleotides. Proc Natl Acad Sci USA. 100:4504-9.]; rolling circle
amplification (RCA); transcription-based amplification system (TAS) and
its derivatives include self-sustaining sequence replication (3SR),
isothermal nucleic acid sequence-based amplification (NASBA), and
transcription-mediated amplification (TMA); ligase chain reaction (LCR)),
sequencing reactions of DNA or RNA (such as Maxam-Gilbert sequencing,
Sanger chain-termination method, Dye-terminator sequencing Emulsion PCR
sequencing, massively parallel sequencing, polony sequencing, sequencing
by ligation, sequencing by synthesis, or sequencing by hybridization),
restriction fragment length polymorphism (RFLP) analysis, single
nucleotide polymorphism (SNP) analysis, short tandem repeat (STR)
analysis, microsatellite analysis, DNA fingerprint analysis, DNA
footprint analysis, or DNA methylation analysis.
[0161]In one embodiment a cartridge employs beads coupled to a binding
moiety, including but not limited to a binding receptor, transferrin, an
antibody or a fragment thereof (such as an Fc fragment or an Fab
fragment), a lectin, or a DNA or RNA sequence. In another embodiment a
cartridge comprises a reagent such as an anti-coagulant, a fixative, a
stabilization reagent, a preservative or precipitation reagent.
C. Pneumatic Manifold
[0162]A pneumatic manifold can be integrated with any microchip and/or
cartridge described herein to facilitate distribution of air pressure or
vacuum. The air pressure or vacuum can be used to actuate valves on the
microchip. Alternatively, air pressure or vacuum can be supplied to a
cartridge such that air pressure or vacuum is provided to microchannels
within the fluidics layer of a microchip which can be used to move fluids
or gases within the fluidics layer. A pneumatic manifold provides the air
pressure or vacuum to operate microvalves on microchip (2) on cartridge
(1) of FIG. 3 or operate microvalves in other devices.
[0163]A pneumatic manifold can be used to mate the pneumatic lines of a
microfluidic microchip to external pressure sources. The pneumatic
manifold can have ports that align with ports on the pneumatics layer of
the microfluidic microchip and ports that can be connected to tubing that
connect to the external pressure sources. The ports can be connected by
one or more channels that allow for fluid communication of a liquid or
gas, or other material between the ports.
[0164]The pneumatic manifold can be interfaced with the microfluidic
microchip on any surface of the microchip. The pneumatic manifold can be
on the same or different side of the microfluidic microchip as the
cartridge. As shown in FIG. 40, a pneumatic manifold (113) can be placed
on a surface of the microfluidic microchip opposite to the cartridge. As
well, the pneumatic manifold can be designed such that it only occupies a
portion of the surface of microfluidic microchip. The positioning,
design, and/or shape of the pneumatic manifold can allow access of other
components to the microfluidic microchip. The pneumatic manifold can have
a cut-out or annular space that allows other components to be positioned
adjacent or proximal to the microfluidic microchip. This can allow, for
example, a magnetic component (109) to be placed in proximity of a
chamber within the microfluidic microchip.
[0165]A pneumatic manifold can be constructed of any material known to
those skilled in the art. For example, the cartridge can be constructed
of a plastic, glass, or metal. A plastic material includes any plastic
known to those skilled in the art, such as polypropylene, polystyrene,
polyethylene, polyethylene terephthalate, polyester, polyamide,
poly(vinylchloride), polycarbonate, polyurethane, polyvinyldiene
chloride, cyclic olefin copolymer, or any combination thereof. The
pneumatic manifold can be formed using any technique known to those
skilled in the art, such as soft-lithography, conventional lithography,
milling, molding, embossing, drilling, etching, or any combination
thereof.
[0166]A pneumatic manifold (370) was designed (FIG. 20) that eliminates
over twenty tubing ports and provides a robust, reproducible interface
between the control system, the pneumatic solenoids and the MOVe input
ports. The manifold (370) has a gasket (380) and a bottom plate (390)
that are fastened together. The cartridge (1) is held on the plate (370)
by a bracket in position to align the pneumatic ports 10, 20, 30, 40, 50,
60, and 70 on microfluidic microchip (2), shown in FIG. 5, with the
pneumatic lines shown of the reverse side of 370 in the FIG. 20 insert.
The external pneumatics are controlled by a solenoid valve bank that can
be miniaturized and can be connected to vacuum or pressure sources.
[0167]The apparatus shown in FIG. 21 and FIG. 22 can incorporate the
pneumatic manifold shown in FIG. 20. The apparatus can be used for sample
preparation, as described herein, and can incorporate a cartridge.
Cartridge (1), labeled `cube`, is attached to manifold (370) with
solenoids (1819). The assembly of the cartridge and manifold is mounted
on a base plate of the apparatus. The pneumatic manifold can be
controlled by an IO controller (1803).
[0168]A gas supply, such as a reservoir that can be maintained at a
desired pressure or vacuum, can supply gas to the manifold. The gas
supply can be connected to an outside pressure or vacuum source. The gas
supply feeding the gas supply manifold can have a pressure gauge to
monitor the inlet pressure. The gas supply can supply gas to multiple
components of the system through a gas supply manifold (1821). The gas
supply manifold can supply gas to the pneumatic manifold (370) and to
individual reagent containers, (1809) and (1807). The line supplying the
distribution valve (390) with gas can be regulated by a regulator (1815).
[0169]Reagents and/or sample can also be supplied to the cartridge through
the reagent distribution valve (390) that is connected to containers
(1809) in a reagent storage region (380) and a bead solution container
(1807) that is mounted on a bead mixer (1805). Adapter (1817) can be
mounted and/or aligned with the cartridge such that a delivery device,
such as a syringe, can deliver a material to the cartridge. The adapter
(1817) can be thermally regulated by a heater control (1801). The adapter
can have a thermal conductor, such as brass, to distribute heat generated
by heater coil or a Peltier device. The adapter can maintain temperature
between about 20 to 100, 20 to 75, or 50 to 60 degrees Celsius.
[0170]A magnet assembly (1811) can be positioned adjacent to the
cartridge. A magnet (300) of the magnet assembly can be positioned
adjacent to the cartridge (1) and moved by an actuator, such that the
magnet can exert a magnetic field within the cartridge, or a microchip
integrated, mated, or interfaced with the cartridge. The magnetic field
can be used to capture paramagnetic or magnetic particles, such as beads,
within the cartridge or microchip and separate material bound to the
particles from waste materials. Waste from the cartridge and/or microchip
can be delivered to a waste container (1813).
[0171]The apparatus shown in FIG. 21 and FIG. 22 can use seven solenoid
valves to operate the cartridge (1). The size and complexity of the
apparatus can be further reduced with MOVe microvalves. FIG. 23 and FIG.
24 shows a reagent distribution device that contains microfluidic
microchip 600, which is approximately two inches wide. Solenoid banks 680
and 684 provide connection to full scale external vacuum and pressure
through connectors 681, 682, 685, and 686. The solenoids are controlled
through electrical junctions 689 and 687. The microfluidic microchip 600,
which has MOVe valves, is held in contact with the manifold 700 by
attachment 711 using clamp 710. Other methods known to one skilled in the
art can be used to connect the microchip to the pneumatics manifold 700.
[0172]As shown in FIG. 25, microchip 600 connects five reagent sources,
621, 622, 623, 624, and 625 with two sample loops 630 and 631 and five
devices 634, 635, 636, 637, and 638 which may be microfluidic devices
such as cartridge (1). Sample loops 630 and 631 can be configured to have
predetermined volumes. The sample loops can have a portion which is
removable. Thus, they can be removably connectable to ports in the
fluidic manipulation module. The sample loop can be removed to allow for
adjustment of the volume of the sample loop. A portion of the sample loop
can be capillary tubing, any other type of tubing, or a microfluidic
channel. The sample loop can be connected to the microchip using any type
of junction described herein. For example, a junction can connect to a
cannula, an upfit tubing, a microtubing fitting, an Upchurch tubing
adapter, or a FROLC connector [Jovanovich, S. B., G. Ronan, D. Roach and
R. Johnston. Capillary valve, connector, and router. Feb. 20, 2001. U.S.
Pat. No. 6,190,616.]. It is apparent that the number of reagent sources,
microfluidic devices, and sample loops can be increased or decreased.
Each microfluidic device can perform the same function, different, or
complementary functions. The devices can be connected through modular
microfluidic ports.
[0173]In an aspect of this invention shown in FIG. 25, a microchip (600)
comprises a main microfluidic channel that intersects with two other
second microfluidic channels. The main microfluidic channel can be a
channel that connects the reagent source 625 with device 634, as shown in
FIG. 25. The second channels can be the channel that connect valve 606 to
the sample loop 630 and the channel that connects valve 608 to sample
630. At least one, and optionally both, of these second channels connects
with the main channel through a flow-through valve (606 and 608) that
allow a fluid to flow through the main channel but only into or out of
the second channel with the flow through valve is open. The flow-through
valve can be redesigned as an in-line valve. The main channel also
comprises an intermediate valve (674) between the points of intersection
of the two second channels. Each second channel opens from the microchip
at an entry port. A sample loop (630) having a channel of defined volume
is removably attached to each of the entry ports. Thus, a specific volume
of fluid in the sample loop can be injected into the main channel by
closing the intermediate valve (674), opening the flow through valves
(606 and 608) and applying pressure to the main channel. The sample loop
can also be referred to as a fluid loop or reagent loop.
[0174]The microchip 600 of the distribution manifold uses eighteen
microvalves 601 to 618 to direct flow through the manifold. The
microvalves are operated through pneumatic ports with o-rings or other
connectors including modular microfluidic ports to pneumatic manifold
700. For example, connection 671 provides pressure or vacuum to
microvalve 641 and connection 673 provides pressure or vacuum to
microvalve 642. The flow of reagents from reagent sources, 621, 622, 623,
624, and 625 can be directed to fill the sample loops individually or to
move samples to devices 634, 635, 636, 637, and 638.
[0175]The pneumatics on manifold 700, as shown in FIG. 26, connects
pressure sources 685 and vacuum sources 686 through solenoid banks 680
and 681 to pneumatic channels 683 leading to the array of ports 684 that
includes ports 671 and 673. The top portion of FIG. 26 shows the
pneumatic lines of the pneumatic manifold that lead into the pneumatic
layer of a microchip from the solenoids. The bottom portion of FIG. 26
shows the solenoids and vacuum (685) and pressure source (686) that are
connected to each solenoid. The solenoid banks are controlled by
electronics to open and close each individual solenoid to the common
vacuum or pressure sources. The individual vacuum or pressure control is
also envisioned.
[0176]The pneumatic manifold 700, shown in FIG. 23, can operate the
microvalves 601 to 618 on microfluidic microchip 600, shown in FIG. 25.
For example, to move a reagent from reagent source 622 to sample loop
630, microvalves 602, 606, and 608 are opened and pass-through valve 658
is closed. Alternatively, reagent can by-pass sample loop 630 by closure
of T-valves 606 and 608 and opening pass-through valve 658. The valves
can be controlled by pneumatic lines that are fluidically connected to
the pneumatic manifold. For example, pneumatic line 672 is controlled by
a solenoid on pneumatic manifold 700, shown in FIG. 23, to open or close
the microvalve 642. Valves 603, 604, 605, 609, 610, are always open to
flow through the microfluidic circuit containing microchannels 641 to 644
and 656 to 668. The reagent is moved into sample loop 630.
[0177]The circuit between 622 and 612 can be overfilled if desired or
precisely controlled by MOVe microvalves to modulate flow or control of
timing. Once the sample loop 630 is filled, a defined volume has been
selected. The microfluidic circuit can be cleaned by flushing cleaning
solutions or air or gas through the main channel to further define the
reagent volume. If reagent source 621 was a compressed air or gas source
(pressure and vacuum are types of reagents in a pressurized flow system),
opening microvalve 601 and microvalves 606, 610, and 616 creates the
circuit to move the measured reagent in sample loop 630 to device 636. In
one embodiment a means to connect any number of reagent sources to a
microdevice such as cartridge (1) is provided.
II. Parallel Processing of Samples
[0178]In some embodiments of the invention, one or more cartridges can be
operated simultaneously to allow for parallel processing of samples. FIG.
16 illustrates parallel or ganged operation of multiple cartridges with
microvalves on a single pneumatic manifold in swab extraction assembly
(800). The manifold (370) distributes regulated vacuum and pressure to
operate four cartridges (1), indicated in the figure, using solenoids
(680). Solenoids (680) control pressure to the pneumatic layer of a
microchip integrated with each cartridge through the pneumatic manifold
(370, 380, 390). The pneumatic manifold is formed by a top plate (370), a
gasket (380) and a bottom plate (390). The top plate can have channels
etched into it. The channels can be sealed by the gasket, which is
sandwiched against the top plate by the bottom plate (390). Actuator 310
moves rod 810 to move magnets (320) close to or away from the cartridges
(1). Clamps 805 hold cartridges (1) in place.
[0179]In other embodiments of the invention, a single cartridge integrated
with a microchip can process multiple samples at one time using parallel
channels. FIG. 14 and FIG. 15 shows an assembled capture and reaction
microchip with capillary feed and magnets. This microchip can capture
bead solutions and perform four STR-PCR reactions simultaneously. FIG. 14
shows a microchip (1201) with a cartridge (1203) adhered to the microchip
and tubes (1205, 1207, 1209, 1211, 1213, 1215, 1217, and 1219) leading
into and out of the microchip. A total of eight tubes are shown and two
tubes are used per parallel reaction. For example, one unit of the
parallel processing device is served by tubes 1205 and 1213.
[0180]In another embodiment, a four-channel sample preparation device
(FIG. 66) combines a four-channel parallel reagent delivery device (FIG.
67) that meters and delivers reagents simultaneously to all four channels
of a single integrated cartridge (FIG. 68) enabling four samples to be
processed simultaneously and rapidly.
[0181]The four-channel parallel reagent delivery device combines an Chip C
microchip (see FIG. 67) with a fluidics manifold mounted on a pneumatics
control manifold. Reagents are metered, using one of the two different
size reagent loops, which can be similar to the sample loops described
herein, for each channel, and delivered in parallel to all four channels
of the sample preparation device. Delivering reagents simultaneously to
all four channels of the sample preparation device using the parallel
reagent delivery device can takes <4 minutes, representing a process
time saving of >11 minutes as compared to the first generation serial
reagent delivery device that took .about.15 minutes per four samples
processed.
[0182]Bonded pneumatics manifolds can be used to control both the reagent
delivery and sample preparation devices by fabricating the manifolds
using an adhesive bonding approach; however, these may be prone to
delamination over time due to the pneumatic pressures used in the
subsystem, and the size and complexity of the manifold. Thermally bonded
manifolds can mitigate delamination issues, but may only be a viable
approach for relatively small and low complexity manifold designs such as
the reagent delivery device. A monolithic manifold made from a single
piece of polycarbonate with tubing connecting pneumatic ports to the
solenoid control valves can operate the four-channel sample preparation
cartridge and has proved to be a viable alternative to bonded pneumatic
manifolds, see FIG. 45 and FIG. 46 for examples. This pneumatic manifold
design concept is also being utilized for control of the Chip A microchip
on the Post-amplification STR (Single Tandem Repeat) clean-up subsystem.
[0183]Assembly processes for the microchip and fluidic manifold of the
four-channel sample preparation cartridge have also been improved.
Historically, silicon epoxy can be used to attach the cartridge to its
associated MOVe microchip by wicking the adhesive between the microchip
and the cube. An inherent lack of control of the movement of the epoxy
can allow it to occasionally wick into the ports on either the microchip
or the cube creating a blockage in the fluidic pathway rendering the
device unusable. This process has been improved by using a double-sided
adhesive tape (Adhesives Research ARcare90106) to assemble the fluidic
cubes and microchips; this is now the preferred assembly method used for
the four-channel reagent delivery cartridge, the sample preparation
device, and the post amplification device in the Post-amplification STR
clean-up subsystem described below.
[0184]The integrated four-channel sample preparation cartridge with the
Chip D microchip (see FIG. 69) was tested. The Chip D microchip, shown in
FIG. 69 on the left panel, highlighted an issue with the design wherein
the PDMS membrane inadvertently closed off fluidic channels adjacent to
flow through valves on the MOVe microchip. Without being limited to
theory or conjecture, it is thought that this effect is due to a
combination of variables including minor differences in alignment during
microchip assembly, the etch depth of the microchip's fluidic layer, and
the pneumatic pressure used to operate the microchip on the sample
preparation device. A microchip, Chip E, shown in FIG. 69 right panel,
was been designed to convert all flow through valves that form a
T-junction between two bisecting channels in the Chip D microchip, to
in-line channel that have only one channel passing through the middle of
the channel. The Chip E microchip can reduce the occurrence of
inadvertent channel closure during valve closure. In FIG. 69, left panel,
the four circles in that are positioned along the middle of the microchip
can be operated independently and are each fluidically connected to a
swab extraction device that can be used to extract analytes from a swab.
Other ports in the microchip can connect to chambers in a cartridge
(similar to the ports and chambers described for FIG. 3 and FIG. 4) that
are mated to the microchip (shown in FIG. 68) for performing reactions,
such as nucleotide binding. Operation of the integrated four-channel
sample preparation cartridge with microchip is similar to the operation
of the device shown in FIG. 3 and FIG. 4.
[0185]Microchip blockages due to the inadvertent introduction of fibers
into the systems and devices described herein can be problematic in
microfluidics. To minimize blockages, all reagents with the exception of
paramagnetic bead solutions, can be filtered prior to loading and in-line
filters used to minimize microchip blockages.
[0186]Subsystem testing of the second-generation sample preparation device
focused on characterization of system reproducibility and failure modes.
A total of 80 samples were processed on the subsystem with a success rate
of 63%. Failure modes included Reagents line accidentally becoming
disconnected (2.5%), chip blockages (3.75%), no STR profiling observed
(9%), and DNA yield <0.08 ng (22%), which is the limit of detection of
the downstream system. The average yield of purified DNA yield was found
to be 0.26 ng. Approximately half of the samples tested in STR reactions
gave full profiles and half gave partial profiles (see FIG. 70). A number
of blank samples were processed on the system using cleaned and recycled
cartridges, and run-to-run cross contamination was found to be
negligible.
III. Integrated Sample Preparation and Polymerase Chain Reaction
[0187]In some embodiments of the invention, a cartridge can be integrated
with devices for performing polymerase chain reaction and product
analysis. Such a device is shown in FIG. 6. FIG. 6 shows a cartridge with
integrated microchip (1), temperature modulating device (400), and
downstream analysis device (500). In certain embodiments the device
comprises a fluid preparation module comprising a cartridge mated or
otherwise fluidically connected to a microchip; an off-chip thermal
modulation module connected to the fluid preparation module through a
fluid transporter with a fluidic channel, such as a tube, through the
cartridge, and configured to modulate the temperature in the fluid
transporter, wherein the fluid transporter is further fluidically
connected to a second microchip with valves and fluidic channels that can
selectively route fluid to one or more subsequent devices. This device
can be used for thermal cycling or isothermal reactions.
[0188]The cartridge with integrated microchip can be formed of any
cartridge and microchip described herein. For example, the cartridge and
microchip shown in FIG. 3, FIG. 4, and FIG. 5. A movable magnet (300) can
be positioned adjacent to the cartridge. The movable magnet can be moved
by an actuator (310). The movable magnet can be used to apply a magnetic
field within the cartridge or the microchip. In some embodiments, the
movable magnet can be used to facilitate gathering or collecting of beads
against a wall of a chamber within the cartridge or the microchip.
[0189]A temperature modulator can be fluidically connected to the
cartridge and microchip through reaction channel (250). The reaction
chamber (250) can be connected at an end (251) to the cartridge. The
temperature modulator can be used for thermal cycling the temperature of
a reaction channel (250) containing a reaction mixture and a nucleic acid
enriched from a sample (collectively referred to as the PCR reaction
sample). A control mechanism can be used for controlling the operation of
the temperature modulator. An optical assembly can be used to monitor or
control the reaction. The optical assembly can introduce or detect light.
For example, an optical assembly 410 can be used for performing Real-time
PCR or other real-time or end point measurements. In certain embodiments
the temperature modulator employs a thermo-coupled Peltier thermoelectric
module, a conventional thermoelectric module,
hot air, infrared light or
microwave. In one embodiment the temperature modulator uses a Peltier
thermoelectric module external to the reaction channel to heat and cool
the PCR reaction sample as desired. The heating and cooling of the
thermoelectric module can be distributed over a region 350. Additional
views of the temperature modulator 400 are shown in FIG. 7 and FIG. 8.
FIG. 7 shows the reaction channel 250 in contact with a temperature
controlled region 350. The temperature modulator can also include a
movable magnet 320 that is positioned by an actuator 330. The movable
magnet can be used to capture magnetic particles at position 340, as
shown in FIG. 6. In some embodiments of the invention, the temperature
controlled region comprises two parts. The two parts can be parts of a
clamshell that are clamped, locked, or held together to maintain thermal
contact with the reaction channel 250. One portion of the temperature
controlled region, portion 711 of FIG. 8, can be hinged to the second
portion of the temperature controlled region. The temperature controlled
regions can have grooved channels for positioning of one or more reaction
channels, as shown on the right side of FIG. 7 and in FIG. 8. The left
side of FIG. 7 shows the temperature controlled region in a closed
configuration. Additionally, the temperature controlled region can
comprise one or more constriction components, shown as 709 and 701 in
FIG. 8. The constricting points can pinch the reaction channel such that
a portion of the reaction channel is isolated from another portion of the
reaction channel. In some embodiments of the invention, the reaction
channel is pinched in two locations such that a body of fluid, such as a
reaction mixture, is isolated. Constriction components 709 and 701 can
mate with additional constriction components 707 and 705 to facilitate
pinching of the reaction channel.
[0190]Alternatively the temperature modulator can constrict the reaction
tubing using an pinch clamp, as shown in FIG. 65. Use of the pinch clamp,
which can be formed of a plastic such as Ultem, can reduce heat transfer
to the reaction channel. The reduction in heat transfer can reduce the
likelihood that the reaction channel has for being welded closed during
thermocycling or temperature regulation. Alternatively, different
material tubing can be used as the reaction channel to ensure that the
reaction channel can maintains its shape before and after the
thermocycling or temperature regulation process. Different material
tubing can also be used to reduce rate of evaporation during the
temperature modulating process. Example materials include ethylvinyl
acetate, silicone, and silanized c-flex tubing.
[0191]The temperature modulating device can modulate temperatures at a
rate of 0.5 to over 3 degrees Celsius per second. The heater can utilize
about 25 to 100 Watts and a fan, which can be used to cool the
temperature modulating device, can produce an air flow rate of at least
about 75, 100, 130, 150, 200, 250, or 300 cfm.
[0192]In one embodiment a sample preparation device comprising a cartridge
integrated with a microfluidic microchip 1, which can be used to control
the movement of fluid in the cartridge, can be used in conjunction with a
temperature modulator 400 as a flow-through PCR thermal cycler. Driving
force for moving the fluid can be an external pressure source or an
internal pressure source, such as a MOVe valves within the microchip. A
flow-through PCR thermal cycler can be used when highly sensitive or high
throughput PCR is desired. There are many situations in which one might
want to sample air, blood, water, saliva, a cellular sample, or other
medium in a sensitive PCR assay. This can be used to look for a variety
of biological contaminants including influenza, bacterial pathogens, and
any number of viral or bacterial pathogens. Flow-through PCR can allow
PCR to be practiced in an automated manner without the need for human
interaction. A flow-through PCR system can also serve as an early warning
system in HVAC systems of buildings, airplanes, busses, and other
vehicles, and can be used in the monitoring of blood, water, or other
sample sources for the presence of an infectious agent or a contaminant.
[0193]As shown in FIG. 6, the flow-through PCR device takes a sample from
a collection device, such as a buccal swab, a syringe, an air sampler,
fluid sampler or other sampler and delivers it to a sample preparation
device 1. FIG. 6 is not necessarily drawn to scale. The sample is
prepared in the preparation device 1, which in some embodiments may
include cell lysis, DNA, RNA, or micro RNA enrichment or purification,
filtration, or reverse transcription. In one embodiment at least one
nucleic acid is enriched. In another embodiment at least one enriched
nucleic acid is prepared for PCR by adding the nucleic acid to PCR
reagents (such as at least one DNA polymerase, RNA polymerase, dNTPs,
buffer or a salt) and primers, (such as assay-specific primers or broadly
applicable primer sets for multiple target pathogens). These primers may
be chosen to selectively amplify at least one nucleic acid isolated from
a specific pathogen (such as a mold, virus, bacteria, parasite or
amoeba), gene, other desired nucleic acid, or any combination thereof.
The composition comprising at least one nucleic acid enriched from a
sample, PCR reagents and primers is called a PCR reaction sample. In one
embodiment, the flowthrough PCR can be used as a continuous flow device
while in other embodiments samples are moved into the thermal cycling
region and stopped.
[0194]The PCR reaction sample then flows through a reaction channel (250)
to a temperature controlled device or region (350). In some embodiments
the reaction channel is clear or transparent. In another embodiment the
reaction channel is opaque. In one embodiment the reaction channel is a
cylinder. In another embodiment the reaction channel's cross section
comprises one or more planes forming a shape such as a triangle, square,
rectangle, pentagon, hexagon, heptagon, octagon, nonagon, decagon, or
other polygon. In one embodiment the volume of PCR reaction sample is
such that it takes up a small discrete length of space in the reaction
channel, the rest of which is occupied by air, gas, or a non-reactive
liquid, such as mineral oil. Air, gas, or a non-reactive liquid can be
used to separate individual PCR reaction samples from each other. In one
embodiment the temperature controlled region (350) is thermally modulated
by one or more modules, including but not limited to thermo-coupled
Peltier thermoelectric module, a conventional thermoelectric module,
hot
air, microwave, or infrared light. In one embodiment the thermal cycler
uses Peltier thermoelectric modules external to the tube to heat and cool
the sample as desired. In one embodiment a detection module (410)
measures fluorescence, luminescence, absorbance or other optical
properties to detect a signal emitted from a PCR reaction sample while it
is located with a temperature control region, or after it has left a
temperature control region. A detection module can comprise a light
source (such as a coherent light source or incoherent light source) used
to excite a fluorescent dye (such as an intercalating dye, including but
not limited to ethidium bromide or Syber green) in a PCR reaction sample,
and the excitation light is sensed with a p
hotodetector (such as a CCD,
CMOS, PMT, or other optical detector). Detection electronics can evaluate
the signal sent from the detection module (410).
[0195]In one embodiment, after the desired number of thermal cycles are
complete, the PCR reaction sample is pumped or pushed further down the
reaction channel, using pressure or vacuum, exiting the temperature
controlled region and passing into a second microfluidic microchip (500).
The second microchip (500) can be attached at end (252) to the reaction
channel (250). Microfluidic microchip (500) can comprise microvalves
(510, 520, 530, and 545). Any three microvalves such as 510, 520, and 530
or 510, 520, and 545 can form a pump. Microchannels 505, 515, 525, and
540 can connect the pumps on the microchip. Downstream devices 535 and
550 can be connected to the microchip. Flow of material to devices (535
and 550) can be controlled by the microvalves, for example, by keeping
either valve 530 or 545 closed while pumping or moving fluid. In one
preferred embodiment, the downstream device are analytical devices that
can be used for performing electrophoresis, mass spectroscopy, or other
analytical techniques known to one skilled in the art.
[0196]In one embodiment the second microfluidic microchip can deliver the
PCR reaction sample to a module or region for further processing or
analysis. In another embodiment multiple reaction channels may be used in
parallel to increase sample throughput. In yet another embodiment the
system may alert the user when amplification has occurred (a positive
result), indicating that the target sequence is present. In one
embodiment a reaction channel is used for a single use only, then
disposed of. In an alternative embodiment a reaction channels can be used
to amplify and detect the presence or absence of PCR amplification
products in multiple samples. More than one PCR reaction samples can be
loaded at intervals and interspaced with a barrier bolus of gas or liquid
to prevent intermixing. In one embodiment samples are spaced apart in a
manner so that as one is undergoing thermal cycling another sample is in
the detection region undergoing interrogation. It will be obvious to one
skilled in the art that the PCR amplification can be replaced by other
nucleic acid amplification technologies which may use thermal cycling or
be isothermal reactions.
[0197]In other embodiments, the device can perform isothermal reactions
such as sandwich assays using affinity reagents such as antibodies or
aptamers to determine if cells, proteins, toxins, or other targets are
present with the detection module (410) providing a reading of the amount
of target present. In these applications, the cartridge 1 may perform an
affinity purification such as an IMS purification and then add a
secondary antibody that may have a fluorescent label attached. The sample
can then move into region 350 where the thermal control is set to
optimize the reaction. Detection module (410) can then monitor the
reaction. In one embodiment, a plurality of cartridges are ganged to
reaction channel (250) and a series of boluses can be readout with
detector 410.
IV. Device for Capillary Electrophoresis
[0198]In one embodiment a complete sample-to-answer system is used, which
can comprises microfluidics, requiring coupling all steps together to
match volumes and concentrations. Sample analysis using capillary
electrophoresis is a standard analytical method that can be used with
microfluidic sample preparation methods as described above. Capillary
electrophoresis is readily adaptable to microfluidic microchips. In the
instant invention, capillary electrophoresis on microchips is combined
with MOVe valves to provide control of samples, process beads to
concentrate the samples, and improve the loading and separations.
[0199]In one embodiment the Twin-T injection system is used in the design
of the microfluidic injector for separations. In an alternative
embodiment a design is used for the Forked Cathode injector (FIG. 30).
The layout is similar to the Twin-T in that the sample plug is described
by a section of channel adjacent to the separation channel but key
differences exist. First, the cathode channel is divided into two parts,
this splits the injection electrically into two parts and thus doubles
the quantity of material injected for a given sample plug dimension.
Second, the sample channel and separation channel are at right angles to
one another. This allows the sample channel to be straight and filled
with buffer (rather than separation polymer), which facilitates
manipulating the contents of this channel with pumps and fluid flows, and
allows the separation polymer interface to be sharp. Lastly, the injector
can be run in a mode that allows Field Amplified Sample Stacking (FASS).
[0200]FIG. 30 shows an example of a forked cathode injector that utilizes
microchannels as the forked cathode. As shown in FIG. 30, a sample is
moved electrokinetically across a sample loading channel (shown in the
drawing on the lower left with the arrow through it). Then the sample is
driven into the separation channel (the vertical channel) by applying a
field between it and the cathode arms (the two channel dropping down)
while pull back is applied to the sample and waste. The initial sample
plug dimension is defined by the distance between the cathode arms. The
configuration of the channels allows for a more reproducible plug and
better integration with MOVe microfluidic systems.
[0201]In an aspect of the invention shown in FIG. 30, fluidic channel 3003
is in electrical contact with forked electrodes 3001 and 3002. The points
of contact of the electrodes with the channel are spaced apart, thereby
creating a segment in the channel in which there is an electric field.
Separation channel 3004 intersects fluidic channel 3003 at a point in the
segment between the points of contact of the forked electrodes. Another
electrode of opposite charge is put in electrical contact with the
separation channel. In this way, a voltage is applied through the
separation channel.
[0202]FIG. 62 show a sample source 6009 connected to a sample channel
6005, also referred to as a loading channel, that is mated with a
separation channel 6011. Two electrodes, 6003 and 6001, can be used to
apply an electric field to the separation channel. In some embodiments of
the invention, the sample source can pass through a MOVe pump in a
microchip used to drive fluid flow within the sample channel. The sample
channel can be a microfluidic channel or an injection tubing. The
injection tubing can be flexible tubing or another flexible connector.
Examples of flexible tubing include polytetrafluoroethylene tubing or
silicon tubing. The flexible connector can also connect to another
cartridge interfaced with a microchip. Alternatively, the flexible
connector can return to the cartridge that it originated from. The
separation channel can be a microfluidic channel, capillary tubing, or
capillary electrophoresis tubing. The capillary tubing can have an outer
diameter of about 150 to 500 microns and an inner diameter of about 10 to
100 microns. The capillary can be polyimide or polytetrafluoroethylene
clad. The capillary can be about 2 to 100 cm long. The capillary can be
mated to the injection tubing or flexible tubing by first drilling a hole
into the injection tubing and then inserting the capillary into the
flexible tubing. Alternatively, the capillary can be inserted into the
flexible tubing without having to pre-drill the flexible tubing.
[0203]One of the two electrodes, for example electrode 6003, can be a
cathode and the other electrode, for example 6001, can be an anode. The
cathode can be any cathode, such as a forked cathode, described herein.
The anode can be connected to the separation channel using any devices
known to those skilled in the art. For example, the separation channel
can be joined to a reservoir by an Upchurch fitting, which is in
electrical contact with the anode, which can be a metallic electrode.
[0204]In some embodiments of the invention, a stabilizing component, shown
at the intersection of a separation capillary and injection tubing in
FIG. 63, can be used to align, seal, and/or protect the connection
between the separation capillary and the injection tubing. In some
embodiments of the invention, multiple injection tubings are aligned with
multiple separation capillaries using a stabilizing component. As shown
in FIG. 64, the stabilizing component can hold four injection tubings,
shown as the vertical tubings in the figure, and stabilize the connection
with four separation capillaries (not shown).
[0205]Panels 1-6 of FIG. 62 show a process for injecting a sample into a
separation channel. In panel 1, no sample is present in the sample
channel 6005. In panel 2, sample entering the sample channel from the
sample source (6009) is shown. As sample is moved down the sample
channel, the sample intersects the separation capillary, as shown in
panel 3. The sample can be isolated by boluses of gas upstream and
downstream to the sample. Once sample is adjacent to the separation
channel, an electric field, which can be between 25 and 500 V/cm, is
applied between a first electrode 6003, which can be a cathode or a
forked cathode, and a second electrode 6001, which can be an anode.
Electrophoresis buffer, shown entering into the sample channel from the
sample source, can also enter the sample channel, as shown in panel 3.
The voltage potential and/or current between the anode and cathode can
drop when an air bolus passes by the junction between the sample channel
and the separation channel, reducing or preventing the injection of air
into the separation channel. The voltage potential and/or current drop
can be detected to ascertain when the sample and/or electrophoresis
buffer is adjacent to the separation channel. Once the electrophoresis
buffer is adjacent to the separation channel, as shown in panel 5, the
current and/or voltage drop between the anode and cathode can be
increased. This can allow for the separation of the analyte in the
separation channel, as shown in panel 6, as the electrophoresis buffer
provides ions for a high performance separation.
[0206]FASS is a chromatographic technique that uses the increase in the
electric field caused by areas of low conductivity to increase analyte
mobility in the sample area and concentrate the analyte at an interface
of an area of lower mobility, i.e., at the separation matrix. The net
effect of running the injector in this manner can be seen in FIG. 31.
Significant decrease of the sample plug length, herein referred to as
stacking, can be observed.
[0207]The injector is filled with buffer (dashed line) then the separation
polymer is loaded (solid line) while the interface is swept. The sample
channel (horizontal channel) is filled with sample reaction products in
low ionic strength media. This allows sample stacking and significantly
decreases the sample injection plug size. This is shown in the five
frames on the right of FIG. 31 versus the all polymer injection in the
left panel. The effect of ionic strength and stacking is seen in the
images from second left to right as the buffer dilution increases and the
ionic strength decreases. The sample plug narrows from approximately 300
microns to less than 100 microns.
[0208]In one embodiment for STR analysis the injection process is as
follows: [0209]The microfluidic channels can be filled with buffer.
[0210]The separation channel can be filled with gel while buffer is
pulled across the sample channel, thus sweeping the separation polymer
from the cross section formed by the separation and sample channels.
[0211]The STR amplified sample (desalted and captured on beads) can be
captured on microchip 500, eluted in a low conductivity fluid (water)
containing the size standard, and pumped into the sample channel with
MOVe technology. [0212]A field can be applied across the cathode and
anode, with "pull back" voltage on the sample and waste arms, to drive
the sample into the separation channel where it stacks at the head of the
separation polymer. [0213]As the sample is injected the conductivity of
the sample channel can quickly equilibrate with the buffer in the cathode
arms providing a single step injection.
[0214]The MOVe controlled Forked Cathode injector design (FIG. 32) can be
optimized for DNA separations in microchip channels. In addition to the
FASS described above, the unique integrated injector design also
incorporates the MOVe pumping system which facilitates the use of
magnetic bead technology to desalt and concentrate samples.
[0215]Purified STR amplification products are eluted from magnetic beads,
heat denatured and pumped through the loading channel of the Forked
Cathode injector. A voltage regime is applied to facilitate an FASS
injection at the head of the polymer column, and DNA separation is
performed in a polymer filled micro-channel (FIG. 33). In FIG. 33, the
photos show the movement of dye in the injector in order to illustrate
the STR sample injection mechanism. Field amplified stacking occurs at
the polymer head when injection is initiated.
[0216]Alternatively, the forked electrode or cathode can be two metallic
conductors, as shown in FIG. 60. The fluid path for a sample to be
analyzed, as shown in FIG. 60, can be along a loading channel. When the
location of the sample is adjacent to the separation channel, the forked
electrode can be used to inject the sample into the separation channel,
as described herein. The conductance of the material in the sample
channel can be lower than the conductance of the material in the
separation channel, which can be a separation polymer. The difference in
conductance can cause sample stacking when an electric field is applied
through the forked electrode, which can be a cathode, and a downstream
electrode, which can be an anode. The polarity of the forked electrode
and the downstream electrode can be reversed such that the forked cathode
is the anode and the downstream electrode is the cathode.
[0217]In some embodiments of the invention, an additional electrode can be
used to reduce injection of gas into the separation channel or formation
of bubbles within the sample loading channel which can lead to loss of
the applied field on the separation channel. Injection of gas into the
separation channel or formation of bubbles within the sample loading
channel can cause inconsistent separation of analytes and can be detected
by inconsistent current between the anode and cathode used to apply an
electric field to the separation channel. Use of an additional electrode
to circumvent or reduce injection of gas or bubbles into the separation
channel is shown in FIG. 61. The additional electrode can be a single
wire run electrode or a cannular run electrode. The increased surface
area and/or larger internal diameter of the cannular run electrode can
allow for a significant reduction in bubble formation or blockage and/or
injection into the separation channel. In some embodiments of the
invention, the cannula used for the cannular run electrode and has an
inner diameter of at least about 1/64, 1/32, 1/16, 1/8, or 1/4 inches.
V. mRNA Amplification
[0218]The devices of the invention can be utilized for microarray sample
preparation processes. Gene expression microarrays monitor cellular
messenger RNA (mRNA) levels. However, mRNA can constitute only 1-3% of
cellular total RNA. The vast majority of cellular RNA is ribosomal RNA
(rRNA), and these molecules may interfere with mRNA analysis by competing
with mRNA for hybridization to microarray probes. Any mRNA amplification
method can be performed by the devices described herein, for example
LAMP, TLAD (Eberwine), and MDA. In some embodiments of the invention,
isothermal mRNA amplification methods can be performed using the devices
described herein. In other embodiments, thermal cycling can be performed
to accomplish PCR or cycle sequencing.
[0219]The Eberwine mRNA amplification procedure specifically targets
polyadenylated mRNA (polyA+mRNA) for amplification, virtually eliminating
rRNA interference. This characteristic removes any need to pre-purify
mRNA from total RNA, which can be an inefficient, time-consuming, and
expensive process. In addition, by greatly increasing the amount of
target RNA (that is, amplified mRNA or aRNA) available for microarray
hybridization, mRNA amplification can allow much smaller samples (fewer
numbers of cells) to be analyzed. This can be helpful because the
relatively large amount of target RNA required for microarray analysis
(typically 15 ug) is frequently difficult to obtain. Moreover, it can be
essential in many important clinical diagnostic applications analyzing
samples containing few cells, for example, samples derived from fine
needle aspirates (FNA) or laser capture microdissection (LCM).
[0220]Any process that alters relative mRNA abundance levels may
potentially interfere with accurate gene expression profiling. An
important aspect of the Eberwine amplification procedure is that it
employs a linear amplification reaction that can be less prone to bias
mRNA populations than exponential amplification methods such as PCR.
[0221]The original Eberwine protocol has been streamlined and simplified
by commercial vendors such as Ambion. As shown in FIG. 44, the Ambion
procedure comprises three binary (two component) additions followed by an
RNA purification process. Each binary addition can be followed by
incubation(s) at specific temperatures, as indicated in FIG. 44. The
initial reverse transcription (RT) reaction can have three inputs
(primer, total RNA, and reverse transcriptase [RT] Mix); however, total
RNA and primer can conveniently be premixed. Typical volumes for this
first reaction can be 5 ul RNA+Primer 5 ul RT Mix. Only mRNA hybridizes
to the oligo dT primer and is transcribed into DNA. The second-strand
reaction can be initiated by addition of 20 ul of a Second-Strand Mix,
and the final T7 amplification reaction can be initiated by addition of
30 ul of a T7 Mix. Synthesized RNA can be labeled at this stage by
incorporation of biotin-labeled ribonucleotides. Mixes contain buffers
(Tris), monovalent and divalent salts (KCl, NaCl, MgCl.sub.2),
nucleotides, and DTT, along with enzymes as indicated. Typically, enzymes
can be premixed with concentrated mixes just prior to use.
[0222]After synthesis, aRNA can be purified to remove enzymes, buffers,
salts, unincorporated nucleotides, pyrophosphate, etc. Purification
typically relies on commercial kits exploiting the association of aRNA
with silica membranes or beads in the presence of chaotropic salts such
as guanidinium hydrochloride (GuHCl) or thiocyanate (GuSCN). After
binding, the silica is washed with 70% ethanol (EtOH), dried, and aRNA is
eluted with water.
[0223]Each of these steps can be carried out on the devices described
herein (See U.S. Provisional Patent Application No. 61/140,602). For
example, reagents and sample can be supplied through ports in the
cartridge and then delivered to the microfluidic microchip. The on-chip
valves can be used to pump the reagents and samples to chambers and
reservoirs in the cartridge and the microfluidic microchip through
channels. Temperature control can be accomplished using internal or
external heating and cooling devices. The reaction products can be moved
to product outlet ports of the cartridge for further handling.
Alternatively, the reaction products can be purified or separated using
the devices of the invention.
VI. Separation and Cleanup
[0224]A variety of separations can be performed using the devices
described herein. These separations include chromatographic, affinity,
electrostatic, hydrophobic, ion-exchange, magnetic, drag-based, and
density-based separations. In some embodiments of the invention, affinity
or ion-exchange interactions are utilized to bind materials to
solid-phase materials, such as beads. The beads can be separated from
fluid solutions using any method known to those skilled in the art.
[0225]Magnetic separation can be used to capture and concentrate materials
in a single step using a mechanistically simplified format that employs
paramagnetic beads and a magnetic field. The beads can be used to
capture, concentrate, and then purify specific target antigens, proteins,
carbohydrates, toxins, nucleic acids, cells, viruses, and spores. The
beads can have a specific affinity reagent, typically an antibody,
aptamer, or DNA that binds to a target. Alternatively electrostatic or
ion-pairing or salt-bridge interactions can bind to a target. The beads
can be paramagnetic beads that are only magnetic in the presence of an
external magnetic field. Alternatively, the beads can contain permanent
magnets. The beads can be added to complex samples such as aerosols,
liquids, bodily fluids, extracts, or food. After (or before) binding of a
target material, such as DNA, the bead can be captured by application of
a magnetic field. Unbound or loosely bound material is removed by washing
with compatible buffers, which purifies the target from other, unwanted
materials in the original sample. Beads can be small (nm to um) and can
bind high amounts of target. When the beads are concentrated by magnetic
force they can form bead beds of just nL-.mu.L volumes, thus
concentrating the target at the same time it is purified. The purified
and concentrated targets can be conveniently transported, denatured,
lysed or analyzed while on-bead, or eluted off the bead for further
sample preparation, or analysis.
[0226]Separations are widely used for many applications including the
detection of microorganisms in food, bodily fluids, and other matrices.
Paramagnetic beads can be mixed and manipulated easily, and are adaptable
to microscale and microfluidic applications. This technology provides an
excellent solution to the macroscale-to-microscale interface: beads can
purify samples at the macroscale and then concentrate to the nanoscale
(100's of nL) for introduction into microfluidic or nanofluidic
platforms. Magnetic separations can be used as an upstream purification
step before real-time PCR, electrochemiluminescence, magnetic force
discrimination, magnetophoretic, capillary electrophoresis, field-flow
separations, or other separation methods well known to one skilled in the
art.
[0227]The devices of the invention can accommodate the use of magnetic
beads. For example, beads or bead slurry can be supplied to a port of a
cartridge. The beads can be mixed or suspended in solution within the
cartridge using pumping, magnetic fields, or external mixers. The beads
can then be pumped to desired chambers or reservoirs within the
microfluidic device or cartridge. Beads can be captured within a chamber
using a magnetic field. Beads in a solution can be captured as the
solution travels through the magnetic field, or beads can be captured in
a stagnant solution.
[0228]To illustrate methods of use of the cartridge, several examples are
described below. The first example describes processing of nucleic acid
from a buccal swab with paramagnetic beads to purify the sample followed
by PCR amplification and bead purification of the PCR products. A second
example describes performing immunomagnetic separations to purify cells,
proteins, or other antigenic material using a binding moiety coupled to
beads. A third example describes performing molecular biology to prepare
samples for sequencing technologies such as sequencing by synthesis,
sequencing by hybridization, or sequencing by ligation. It would be known
to one skilled in the art that many different chemistries and
biochemistries can be used with the instant invention. These include, but
are not limited to, enzymatic reactions, purifications on gels,
monoliths, beads, packed beds, surface reactions, molecular biology, and
other chemical and biochemical reactions.
EXAMPLES
Example 1
Operation of a Cartridge for Nucleic Acid Purification
[0229]This example refers to the use of a device comprising a cartridge
mated to a microchip. The numbers refer to the cartridge of FIG. 3 and
FIG. 4 mated to a microchip with the circuit architecture of FIG. 5. This
sub-assembly also can be fluidically connected other sub-assemblies in
the instrument of FIG. 6. For reference, a cartridge mated with a
microchip also is shown in FIG. 40 and FIG. 59.
[0230]Nucleic acids can be purified from a wide variety of matrices for
many purposes including, but not limited to, genotyping, identification,
forensics, gene expression, gene modification, microRNA analysis,
ribotyping, diagnostics, or therapeutics. The input sample can be a
solid, swab, liquid, slurry, aerosol or a gas.
[0231]For molecular diagnostics and forensics, swabs are commonly used. A
buccal swab can be taken using a swab with an ejectable tip and the swab
ejected into a syringe attached to connection 7 of FIG. 4. Connection 5
of FIG. 4 leads by tubing or capillary to a reagent manifold that can
select a single reagent from multiple reagents by opening a full scale
valve or by opening a MOVe valve with the reagents either under pressure
or moved by vacuum. MOVe or other micropumps on microchip 2 of FIG. 4 can
also move the fluids or gases.
[0232]In one embodiment, human and other cells in a swab are first lysed
using a buffer with a heated chaotrophic agent and/or other
commercial-off-the shelf (COTS) chemistries in a syringe inserted into
port 7. The lysate is transported to a DNA isolation chamber (FIG. 4 #3)
where paramagnetic beads have been added from a reservoir to adsorb
nucleic acids onto the beads. A moveable magnet is then actuated to
capture the beads onto the side of the isolation chamber where they are
washed automatically using a buffer. The purified DNA, still bound to
beads, is then pumped through a small diameter tube 250 where multiplexed
PCR is performed. Pre-scripted DevLink.TM. software automates the
complete process. The DevLink software defines a set of communication and
command protocols in a standardized automation architecture that is
simpler, more flexible, and quicker to implement than other software
development approaches. The DevLink implementation framework is based on
core technologies that span multiple operating systems, development
languages, and communication protocols. Software drivers wrap individual
smart components of the system, greatly reducing the time needed for
typical de novo system software development. This makes it relatively
straightforward to integrate the operation of multiple system modules
(pumps, valves, temperature controllers, I/O controllers, etc.) that are
either COM- or .NET-based. DevLink provides a professional quality
software development system for prototyping through product release and
maintenance.
[0233]While DNA amplification is useful for positive identification of
microorganisms, samples can be obtained from a wide variety of substrates
and matrices that contain compounds that are inhibitory to DNA
amplification reactions. Raw samples are most often complex mixtures that
can include inhibitors such as hemes, metal ions, humic and fulvic acids,
chelators, DNases, proteases, and molds. While the initial isolation of
target organisms and toxins from the sample matrix by IMS should remove
most of these inhibitors, lysed cell components and lysis agents can also
need to be removed or diluted from nucleic acid samples so that they do
not interfere with successful amplification.
[0234]In one embodiment, a small volume nucleic acid purification is used.
These purification methods can be used with a wide range of samples, such
as blood, to aerosols, to buccal swabs. Paramagnetic beads can be used in
a disclosed device to purify DNA from various sample sources. In one
embodiment a microfluidic microchip can be used to sequence a nucleic
acid using magnetic beads and reagents to purify nucleic acid products
for sequencing in microscale reactions. In one embodiment, the
microfluidic microchip is a 24-channel microfluidic microchip.
[0235]In one embodiment, polyethylene glycol (PEG)-based nucleic acid
purification is used on carboxylated magnetic beads. This PEG-facilitated
process can produce yields of over 80% from upstream immunomagnetic
separations (IMS) captured samples. Development of a universal sample
preparation module (USPM) can partly involve porting the PEG-based
nucleic acid purification onto a device containing a cartridge such as
the devices shown in FIG. 21 or FIG. 16. In another embodiment, Agencourt
Orapure or Promega DNA IQ chemistries are used in conjunction with a
device of the present invention.
[0236]Bead Dispensation and Delivery.
[0237]To purify nucleic acids, paramagnetic beads with different surface
chemistries can be mixed in a reagent container. Pressure is then applied
to send the reagents to connection 5. MOVe microvalves or other valves
may be closed unless referred to as open. To move the paramagnetic beads
into the reaction chamber (3), microvalves 180 and 150 are opened. The
beads are moved through connection 5 into channel 15 which leads to
junction 190 and microchannel 191. Because microvalves 180 and 150 are
open and microvalves 200 and 170, and the other microvalves, are closed,
an open microfluidic connection is from microchannel 191 through
microvalve 180 to microchannel 181 through microchip 152 to open
microvalve 150 and microchip 151 to junction 120. Junction 120 leads to
cone 13 and chamber 3, which can be filled with beads. The volume of
beads supplied to chamber 3 can be controlled by timing the opening of
the reagent valves and the microvalves or by filling and emptying a
sample loop connected to the microchip or the cartridge.
[0238]Commercial bead based chemistries can be used in the disclosed
system, including but not limited to Orapure from Agencourt (Waltham
Mass.) and DNA IQ from Promega (Madison, Wis.). Orapure uses a
carboxylated bead surface and SPRI chemistry while DNA IQ is an example
of a silica bead and chaotrophic chemistry. Other embodiments of
paramagnetic beads or chemistries to process nucleic acids can be used in
conjunction with the disclosed system, including but not limited to beads
with oligonucleotides, locked nucleic acids, degenerate bases, synthetic
bases, conformation, nucleic acid structures, or other hybridization and
specific capture methods.
[0239]Filling Chamber (3) with Beads.
[0240]For Orapure or DNA IQ beads, 450 microliters can be moved into
chamber (3) using three fills of a 150 microliter sample loop 630 or 631.
A movable magnet 300 attached to actuator 310 can then be moved towards
cartridge (1) near the side of 3 to pull the beads to the side of chamber
(3). Magnet size and orientation can be adjusted to generate magnetic
fields appropriate to specific applications. Pressurized air can then be
applied through the reagent manifold with microvalve 180, 150, and 110
open. The opening of microvalve 110 connects from junction 190 which
connects to the reagent manifold through junction 120 and microchannels
121 and 101 to connection 100 which leads through channel 14 to
connection (4) and to waste. The air can move any remaining liquid
through the circuit. Air or other gases can also be used to dry beads,
volatilize solvents, or for bubble-enabled mixing (described herein).
[0241]Bubbling of Gas Through Chamber (3).
[0242]If microvalves 180, 150, and 220 are open, and all other microvalves
closed, the pressure can force air through chamber (3) to channel 9 and
down channel 19 to junction 210 through microchannels 211 and 221,
through open microvalve 220 and microchannel 231 to junction 230, through
channel 16 to connection 6 which can be a vent. This sequence can bubble
air or other gases through chamber (3) and can be used to mix reactions
in chamber (3) or to change the gas phase.
[0243]Moving Liquids and Beads from Chamber (3) to Waste.
[0244]Liquids and beads can be moved from reaction chamber (3) or any
other location to waste. This can be used to wash beads, flush channels,
move liquids or beads to waste. When pressure is applied to connection 6
with microvalves 220 and 110 open, and all other microvalves closed, the
pressure can force air through channel 16 to junction 230 to microchannel
231, through open microvalve 220 and microchannels 222 and 221, though
junction 210, and channels 19 and 9 into reaction chamber (3) and through
junction 120 through microchannel 121, open microvalve 110, microchannel
101, channel 14 and to connection 4.
[0245]The equivalent effect can be obtained by applying vacuum to
connection (4) if connection 6 is a vent without any additional control
of air pressure. The air pressure or vacuum can move any liquids in
chamber (3) to the waste connection 4. When magnet 300 is close to
chamber (3), paramagnetic beads can remain on the side of chamber (3) and
the result is that the liquid is removed. When magnet 300 is far enough
from chamber (3), paramagnetic beads can not remain on the side of
chamber (3) and the result is that the liquid and beads are removed.
[0246]To clean paramagnetic beads, the beads are pulled to the side of
chamber (3) with magnet 300 (see FIG. 6) and the liquid removed to waste.
450 microliters of buffer can be dispensed from the reagent manifold and
added to chamber (3) by opening microvalves 180 and 150. The beads can be
released if desired and then recaptured by moving the magnet 300 and the
liquid then removed. This is repeated for a total of three times to
produce beads ready to process samples.
[0247]Lysis and Extraction of Nucleic Acids from Cells on the Swab.
[0248]A swab can be loaded into a syringe barrel inserted into connection
7 and then be lysed by addition of lysis buffer through reagent
connection 5 with microvalves 180 and 170 opened. In some embodiments
Orapure or DNA IQ chemistries are used.
[0249]Movement of the Lysed Cellular Material to Chamber (3) and Mixing
with Beads.
[0250]The material in the syringe connected to connection 7 can be moved
into chamber (3) by applying pressure to the syringe or by applying
vacuum to vent 6. When vacuum is used, microvalves 170, 150, and 220 are
opened. The vacuum connects through microchannels 231, 221, 211, and
channels 9 and 19 through chamber (3), microchannels 151, 152, 171, and
161 to pull material from connection 7 into chamber (3). When
paramagnetic beads are loaded and cleaned in chamber (3), the lysed
sample material mixes with the beads in chamber (3) with the magnet is
the far position.
[0251]Purification of Nucleic Acids on the Beads.
[0252]The paramagnetic beads are then incubated with the lysed sample.
Continued air or gas flow can aid mixing. The magnet 300 is then moved to
the closed position and the beads are captured on the wall of chamber
(3). The sample lysate can then be removed from chamber (3) to waste and
multiple volumes of wash solution added according to manufacturers'
specifications for the Orapure chemistry or DNA IQ chemistry. The sample
components on the beads have now been purified and are ready for
reactions in the cartridge or exporting to the sample product connection.
In one embodiment the beads are used to enrich a nucleic acid component
from a sample.
[0253]Exporting Samples Through the Sample Product Connection 8.
[0254]The purified sample components on the beads can be moved to
connection 8 by applying pressures on reagent connection 5 with
microvalves 180, 150, and 130 open. In one embodiment, connection 8 is
connected with reaction channel 250 such as C-flex tubing (Cole Parmer)
and additional reactions are performed in the reaction channel.
[0255]Multiplexed PCR Amplification of STR Markers.
[0256]DNA amplification can be performed by PCR amplification. The present
invention enables PCR reactions as well as many other DNA amplification
and modification reactions. The reactions can be performed in chamber
(3), in reaction channel 250 attached to connection 8 which can be a tube
250 (FIG. 3, FIG. 4, FIG. 6), or in another device or microdevice
connected to tube 250. This demonstrates the utility of the sample
preparation for DNA reactions including thermal cycling.
[0257]Capture of Nucleic Acid Containing Beads in a Reaction Channel.
[0258]The purified DNA output through the sample product connection 8 is
moved into a reaction channel 250 at end 251 by applied pressure or
alternatively through vacuum applied to end 252. An actuator 330 moves a
magnet 320 under software control into a position close to bead capture
region 340. Fixed magnets of different sizes and shapes (such as rare
earth magnets) as well as electromagnets or superconducting magnets can
be used. As the solution containing the beads moves through region 340,
the magnetic field attracts the beads to the side of the reaction channel
and holds them in place. The fluid is then followed by air pressure
through reagent connection 5 leaving the beads region 340 in air.
[0259]Addition of Reagents and Movement of Samples into Reaction Region.
[0260]Reagents can be added from the reagent manifold as described. In one
embodiment, reagents are added from end 252 of reaction channel 250. End
252 is attached to a microfluidic microchip 500 comprising microvalves
510, 520, 530, and 540. Any three microvalves such as 510, 520, and 530
or 510, 520, and 540 can form a pump. Microvalve 530 connects through a
microchannel to a downstream device 535, which can connect to tubing
leading to a reagent reservoir. Microvalve 540 connects through a
microchannel to downstream device 545, which can connect to tubing that
leads to a reagent reservoir.
[0261]Reaction mixes (such as at least one DNA polymerase, dNTPs, buffer
and a salt) including but not limited to master mixes and primers, (such
as assay-specific primers or broadly applicable primer sets for multiple
target pathogens), or complete PCR master mixes such as PowerPlex 16 from
Promega (Madison, Wis.) or IdentiFiler or MiniFiler from Applied
Biosystems (Foster City, Calif.) in reagent reservoir 600 can be
delivered by a micropump formed by microvalves 530, 520, and 510 through
tubing 610 and microchannels 531, 521, 511, and 512, into end 252 of
reaction channel 250, as shown in FIG. 6. MOVe microvalves can precisely
position fluids and move the fluid to region 340 where the reaction mix
encounters the beads comprising nucleic acids. Magnet 320 is moved away
from reaction channel 250 by actuator 330 which releases the beads from
the inner surface of the reaction channel 250. The MOVe microvalves on
microchip 500 pump the beads into device 400 with an area of reaction
channel 250 forming temperature controlled region 350. The region 350 can
be held at isothermal temperatures or thermal cycled or other varied as
is well known to one skilled in the art. The region 350 can be a
temperature modulator or thermally coupled to a temperature modulator.
[0262]FIG. 7 shows a temperature control device 400 that is capable of
thermal modulation using a temperature modulator for heating and cooling
to thermocycle the reaction channel. In one embodiment the temperature
modulator comprises a Peltier module, infra-red module, microwave module,
a
hot air module or a light module. In another embodiment a PCR reaction
sample is moved inside the reaction channel past one or more constant
temperature zones.
[0263]FIG. 9 shows the amplification of PowerPlex 16 STR reactions that
have been prepared in a cartridge (1) from buccal swab samples and
processed in reaction channel 250 using the temperature control device
400 in FIG. 7. The STR markers are amplified from standard conditions
with Mg optimized for the apparatus 1000.
[0264]The temperature control device 400 can also have a detector 410. The
detector can detect optical detection such as absorbance, fluorescence,
chemiluminescence, imaging, and other modalities well known to one
skilled in the art or measurement such as IR, NMR, or Raman spectroscopy.
The detector can comprise a light source is used to excite a fluorescent
or luminescent dye in the PCR reaction sample, and the excitation light
is sensed with a photodetector (such as a CCD, CMOS, PMT, or other
optical detector). In one embodiment the light source is a coherent light
source, such as a laser or a laser diode. In another embodiment the light
source is not a coherent light source, such as a light emitting diode
(LED) or a halogen light source or mercury lamp.
[0265]For nucleic acid amplification, real-time PCR is one example of a
nucleic acid assay method that can be performed in tube 250 in
temperature controlled region 350 and detected with detector 410.
[0266]On Microchip Reactions
[0267]In addition to transfer to tubing, apparatus 1000, as shown in FIG.
6, can transfer material to microchips. To facilitate the movement of
this solution onto a microfluidic device for processing a microchip was
specifically designed with large MOVe valves for high volume pumping and
bead capture, stepped ports for interface with input and output
capillaries, side ports for reagent introduction and a 1 .mu.L reaction
chamber. Refer to FIG. 11, FIG. 12 and FIG. 14 for microchip details.
[0268]FIG. 11 shows a microchip schematic. The left depiction in FIG. 11
diagrams the introduction and capture of beads from the cartridge and
apparatus device. The large pump 101 and the magnetic bead capture
chamber 103 are fed by a capillary from the cartridge. Input capillary
indicates where sample is added through the cartridge. Output capillary
indicates where sample is removed through the cartridge. Beads can be
placed in the input capillary and then moved into the magnetic bead
capture chamber by pumping of valves between the input capillary and the
magnetic bead capture chamber 103. Valves are indicated by the dark
circles and opposing triangles. A movable magnet can be positioned
adjacent to the magnetic bead capture chamber to capture magnetic beads
as solution carrying the beads flow through the magnetic bead capture
chamber. The diagram on the right illustrates the resuspension of the
beads and DNA in the STR pre-mix as the sample is moved into the reaction
chamber. The two arrows in the diagram on the right indicate where STR
pre-mix and DNA can be added to the microchip. Valves between the
location indicated by the arrows and the reaction chamber can be used to
pump the DNA or STR pre-mix into the magnetic bead capture chamber for
resuspension of beads, and then into the reaction chamber.
[0269]FIG. 12 and FIG. 13 show bead capture on microchip after transfer
from cartridge device. The bead capture can be performed by using a
magnet positioned adjacent to the microchip such that a magnetic field is
applied within a chamber of the microchip. Shown in FIG. 12 and FIG. 13
is a large capacity (500 mL) MOVe valve, which can be utilized for
pumping and capture of beads. The capture of beads is shown in the inset
with a captured bead bed. As shown in FIG. 13, the magnet 1103 is
positioned over valve 1101 of the microchip. Beads, which can flow into
or out of the valve through fluidic channels 1111 and 1107, are captured
against a wall of the valve due to the magnetic field exerted by the
magnet. The valve can be actuated by a pneumatic channel 1109 that can
deliver a positive pressure or negative pressure, relative to the fluidic
chamber of the valve, causing the elastomeric layer of the valve to raise
or lower.
[0270]One microliter on microchip reactions has been successfully run with
good signal strength and relatively good loci balance. FIG. 17 shows the
results of reactions with using one microliter on microchip reactions as
compared to equivalent off microchip reactions and no template controls
(NTC) that contain only size standards. Peaks represent detection of
nucleotide base pairs.
[0271]Purification of Reaction Products on Beads.
[0272]In one embodiment, the reaction products on the beads can then be
moved into cartridge (1) using vacuum applied to the reagent connection 5
with microvalves 200 and 130 open with the path connecting through 201,
212, 211, to junction 210 and channel 19 and 9 to chamber (3) through
131, 141, and 140 to reaction channel 250. The microvalves on microchip
500 can modulate the vacuum and flow. The reaction products can be moved
into chamber (3) which can be loaded with beads that are cleaned in place
as described above.
[0273]The beads can capture many types of biomolecules using affinity or
other interactions well known to one skilled in the art using bead
purifications, immunomagnetic separations, and reactions with beads,
nanoparticles, quantum dots or other types of particles.
[0274]Continuing the STR example, after STR amplification is complete, the
reaction products are transferred back to the cartridge (1) using vacuum.
Amplified STR products are purified, desalted and concentrated prior to
injection using the same Orapure magnetic bead beads present on the
device for the isolation of DNA from the buccal swab. This time the beads
are used with only ethanol; no PEG/NaCl solution as described previously
for the swab extraction is used.
[0275]The beads are loaded into the cube mix chamber, captured and cleaned
with 70% ethanol. Then the 5-10 .mu.L of STR reaction is pulled back into
the chamber from the cycling zone and into contact with the beads. A 20
.mu.L chase solution of electrophoresis run buffer (chosen because of its
availability on the separation subsystem) is pulled through to scavenge
any remaining STR reaction solution in the reaction channel and 100%
ethanol is added to take the solution up to a 95% total ethanol
concentration.
[0276]FIG. 19 shows data for standard material prepared in this manner on
the swab extractor and analyzed on a MegaBACE. The products were cleaned
with Orapure beads in the sample preparation device configured as a swab
extractor using cartridge (1) and compared to products that were cleaned
using a manually prepared control that had been processed with CleanSeq
(Agencourt). About .about.60% recovery was observed in comparison with
the same process performed off device. It should be noted that the swab
extractor cleaned material yields significantly more efficient injections
than the commonly used process which dilutes the sample by 1:50 to 1:100.
[0277]In another embodiment, a Post-amplification STR clean-up device
delivers the STR reaction premix to the thermocycler; meters the sample
during the isolated DNA bead capture; performs a bead cleanup on the STR
amplified products; delivers the eluted products to the cathode; and
provides reagents to the cathode assembly during preparation of the
separation and detection device and sample injection processes.
[0278]The four-channel Post-amplification STR clean-up device combines an
Chip A microchip, shown in FIG. 47, with an enlarged fluidics manifold
with cleanup chambers (FIG. 71) and mounted on a pneumatics control
manifold (FIG. 72). Agencourt CleanSeq beads are delivered to the
clean-up chamber, the sample is pumped through the reaction tubing 250
from the thermocycler to the clean-up chamber and ethanol is added. The
sample is mixed by air bubbling to facilitate DNA capture onto the beads.
A magnet is actuated at the base of the device cause the DNA and beads to
be captured against the bottom of the clean-up chamber; the remaining
liquid is then pumped to waste. The magnet is moved away from the device
and eluent containing fluorescently labeled DNA size standard in a
formamide solution is pumped into the clean-up chamber. The STR
amplification products are eluted in this solution and the magnet is once
again actuated to capture the beads before the purified and concentrated
sample and size standard are pumped to the cathode, ready for injection
into a separation capillary.
[0279]Testing of the post amplification device using Chip A highlighted
issues with priming and pumping ethanol through the Chip A microchip due
to the high level of resistance in the reagent pathway of this microchip.
The microchip design, Chip E, (FIG. 73) significantly improves
functionality and robustness of the post amplification device by widening
channels and replacing three way MOVe routers with a pair of MOVe
microvalves.
Example 2
Universal Sample Preparation
[0280]The previous example illustrated one embodiment in which the
disclosed apparatus can be used to prepare samples for analysis and
showed one example of STR amplification. Another embodiment involves the
use of a Universal Sample Preparation Module (USPM). The USPM device can
consist of a sample processing cartridge (1), accompanying apparatus to
operate the cartridge, a microprocessor, and software that can readily be
interfaced to downstream analytical devices. In one embodiment the USPM
can be tightly integrated with analytical devices to form a modular
sample-to-answer system. The cartridge can be configured as a disposable
single-use device that can process swabs or liquids (including aerosol
samples) for field monitoring processes, or as a reusable, flow-through
format for remote operations with rare positives. Target specificity of
the USPM is imparted through the use of specific antibodies (that bind
selected targets) attached to paramagnetic beads; different cartridges
can be supplied with various mixtures of targets.
[0281]A USPM can use a multistep fully automated process to prepare
biological samples for downstream analysis. One example in FIG. 18 can
use swabs or liquids; the operator can select the sample type and then
insert samples into input port(s). The first step can apply
immunomagnetic separations (IMS) to capture, concentrate, and purify
target molecules from solution onto paramagnetic beads. Targets already
tested include cells, spores, viruses, proteins, or toxins. For toxin and
protein detection, or for use as a triggering device, the captured
targets from the IMS can be exported directly to the downstream
analytical device. For nucleic acid detection, the second step can lyse
the cells or spores to release the DNA and/or RNA using mechanical or
other lysis techniques. The third step, nucleic acid purification, can
adsorb, concentrate, and purify the nucleic acids onto a second set of
paramagnetic beads and output the beads with nucleic acid, or purified
desorbed nucleic acid, for downstream analysis.
[0282]Referring to cartridge (1), the immunomagnetic separation can be
performed by using reagent beads that have antibodies or other
immunomagnetic, affinity magnetic, or surface chemistry magnetic
separations. For example, immunomagnetic beads with antibodies can be
added to cartridge (1) to capture, purify, and concentrate cells,
viruses, spores, toxins and other biomolecules onto bead.
[0283]Upstream sample processing for the USPM can be done in the sample
preparation devices, which can process samples over 0.6 mL in a
microfluidic cartridge (1) (FIG. 21). The sample processing cartridge,
about 1 in cubed dimension, (FIG. 3, FIG. 21) was developed to
automatically remove collected buccal cells from a swab, lyses the cells,
and purifies released cellular DNA on magnetic beads. The bead beds are
typically 100 nL and can be used for downstream STR analysis with
microfluidics devices or full scale qPCR reactions.
[0284]The sample preparation device uses a MOVe microvalve microchip
interfaced with the bottom of the cube (FIG. 3, arrow labeled 2) to
direct pressure-driven flows consisting of fluids, beads, and samples
among the reagent and reaction reservoirs. The MOVe microvalves replace
conventional valves and tubing between the reservoirs, thereby providing
a non-leakable, directable fluid transport and enable miniaturization of
the entire cube and sample preparation device.
[0285]This sample preparation device technology has been used to automate
DNA extraction from buccal swabs as described above. FIG. 10 shows
automated preparation of DNA from 25 uL of blood in the automated sample
preparation device using pressure driven flows, vibrational mixing, MOVe
valves, actuated magnets, and magnetic beads. The fully automated process
produced DNA ready for STR analysis in less than five minutes.
[0286]We have developed an automated system for capturing, concentrating,
and purifying cells, viruses, and toxins from liquid samples (1-10 mL)
using magnetic beads coated with antibodies specific to targets of
interest. Thus, a variety of targets have been concentrated and purified
with this automated system. Using this approach, E. coli cells were
captured and detected at cell concentrations as low as 15 cells/mL/sample
(FIG. 27). Similar results of greater than 90% capture efficiency were
obtained using Bacillus spores, Gm.sup.+ and Gm.sup.- vegetative cells, a
model virus (bacteriophage fd), SEB, and ovalbumin as targets. Purified
samples can be further processed in the sample preparation device (e.g.,
lysis and nucleic acid purification), moved onto a microchip for
analysis, or used with an off-chip PCR/qPCR device.
[0287]We have shown that IMS capture works well in complex samples such as
aerosols and in the presence of biological clutter (See U.S. Patent
Publication No. 20080014576, herein incorporated by reference in its
entirety). For clutter, we showed that up to 10.sup.5-fold levels of
added bacteria produced only a two-fold reduction in capture efficiency.
For complex samples, add-back experiments using many different aerosol
samples established that aerosol samples reduce the binding of B. cereus
spores to IMS beads by less than 50%. Therefore, there is less than a
two-fold loss of sensitivity in complex, real-world samples.
[0288]We have used IMS to capture, concentrate, and detect toxins. We have
developed IMS assays for ovalbumin and SEB, multiplexed the assays, and
developed two generations of completely integrated microfluidic systems
that automate the IMS assays. Less than 10 ng of SEB can be reliably
detected in a one mL samples with no interference from closely related
Staphylococcal enterotoxins.
[0289]We have shown that IMS can: [0290]Select target organisms from
samples with high backgrounds of interferents (selectivity),
[0291]Discriminate between two different strains or species of bacteria
(specificity), [0292]Effectively capture cells and toxins across a wide
range of concentrations from a wide range of samples (sensitivity,
robustness) [0293]Reduce target sample volume significantly, from mL to
nL volume
[0294]The instant invention and the apparatus and methods are capable of
implementing IMS and coupling it to nucleic acid extractions.
[0295]The next step in the USPM is the lysis of the captured target when
it is a cell, virus, prion, or spore. Lysis of spores is particularly
challenging. A MagMill or magnetically driven lysis or homogenizing
device has been developed for efficient lysis of Bacillus and other
spores, as well as vegetative cells. The MagMill consists of a rapidly
rotating magnet 2000 actuated by a motor 2001 (FIG. 74) that drives
rotation of another magnet 2002 contained within a sample-containing
vessel 2003 or compartment (FIG. 75). The magnet 2002 contained within
the sample-containing vessel can have any shape. For example, the magnet
can have a bar, spherical, cylindrical, rectangular, oval, hexagonal, or
propeller shape. Alternatively, the magnet can have holes through it,
such that liquid may be forced through the holes and increase the shear
force applied to the sample when the magnet is rotated by a magnetic
field. The same basic components can be miniaturized, incorporated into a
microfluidic format, or connected to a microfluidic format. The overall
effect is analogous to a magnetic stir plate, with the sample being
rapidly vortexed within the sample tube. Using magnetically driven sample
agitation by MagMill treatment, spore lysis is achieved without silica,
zirconia or other beads. Lysis may be accomplished by shear forces
generated as the spore passes between the magnet and the vessel walls.
The magnet can rotate at a rate of greater than about 10, 50, 100, 150,
200, 250, 500, 750, 1000, 1500, 2000, 2500, 5000, or 10000 rpm.
[0296]This device disrupts spores with similar efficiency as traditional
bead beating that employs silica/zirconia beads (FIG. 76). Spores
(3.2.times.10.sup.7) were lysed in a volume of 1 ml with viability was
determined by plating on Tryptic Soy Agar; results are an average of two
separate experiments each run with duplicate samples (total n=4). The
non-viability of magnetically-driven spore lysates was 93% compared to
traditional bead beating (BioSpec beater) lysates using either
Zirconia/silica which was 96% or silica beads which was 80%. The same
pattern was confirmed by qPCR
[0297]The advantage of using the MagMill (versus traditional bead beating)
is that the design is more mechanically robust and thus able to withstand
many cycles of use without failure, and samples can be lysed using just
the agitation of the magnet in the sample, without the need for inclusion
of silica/zirconia beads that have been shown to bind released DNA
causing a loss in follow-on detection sensitivity. The basic features of
the MagMill can be reconfigured in a miniaturized format that can be
integrated into a sample preparation device. The system can potentially
be down-sized to fit into a microfluidic microchip. Despite changes in
configuration, however, the principle driving lysis, that of a rapidly
rotating magnet contained within a sample vessel, remains the same.
Example 3
Sample Preparation for Library Construction
[0298]The cartridge (1) technology and the sample preparation device can
be further used to perform a series of complex molecular biology
reactions in small volumes with bead-based manipulation of DNA samples.
The DNA can be processed to prepare genomic libraries for next generation
sequencing systems (i.e., Roche 454 system, or the Applied Biosystems
SOLiD), Real-time PCR, or other DNA assay systems.
[0299]By incorporating a reverse transcriptase step, RNA libraries can
also be converted into DNA libraries by essentially the same method. The
advantage of building an RNA library is that the representation in the
final amplified library will directly mirror the original starting
material since the amplification will be based upon single molecule
amplification.
[0300]The design concept for the Library Construction Module (LCM) is an
instrument that holds bulk reagents and provides fluidic control to the
small disposable Library Construction Module cartridges that processes
individual libraries. The LCM instrument can control fluid flow, mixing,
temperature, and bead manipulation in LCM cartridges through DevLink
software. An array of reagents stored in temperature controlled
reservoirs can be accessible through a MOVe block of valves (actuated by
computer-directed pneumatics 700). Workflow for producing beads with
amplified DNA attached from single molecules is shown in FIG. 29. The
Library Construction Module uses the cartridge as a preferred
implementation.
[0301]MOVe valves are extremely durable, compact, inexpensive compared to
conventional valves, have dead volumes of about 10 nL, and are compatible
with dispensing volumes as low as 100 nL. The instrument can use
pressure-driven flows to move fluids from the reagent reservoirs through
the MOVe valve block, to the reaction chambers in the LCM disposable
cartridge, and out to final sample output vessels (FIG. 25). Reagents and
substrates can be mixed in sample preparation devices using pressurized
flow, vibrational mixing, and pneumatic-driven MOVe valves; magnetic
beads are captured and released using DevLink-controlled actuated
magnets.
[0302]Each disposable LCM cartridge can contain embedded MOVe valves (FIG.
28). The MOVe valves direct fluids from reagent reservoirs and connect
the three reaction chambers. One chamber, the processing chamber A, can
carry out the sequential solution-based molecular biology reactions. The
second, the purification chamber B, can be for bead-based purification of
intermediate products. The third chamber, the annealing chamber C, can
perform the final annealing to glass beads. The annealing chamber can
comprise a filter to separate the beads from surrounding solution.
Pneumatic lines (P1, P2, P3, P4, P5, P6, P7, and P8) can control the
valves of the microchip that control and/or force flow to the chambers.
[0303]Pressure driven flow through the MOVe valves can move fluids between
chambers. The processing and annealing chambers can be capable of mixing
contents and incorporate thermal control.
[0304]In the next sections, the workflow to prepare DNA library samples
using the LCM is described as an example. It is readily apparent that RNA
libraries can be prepared after a reverse transcriptase step.
[0305]Demonstration of Microfluidic Reactions Preceding emPCR
[0306]The starting input for the Library Construction Module can be
nebulized, sheared DNA that has been size fractionated to 800-1,000 bp,
purified, and has already had small fragments (<500 bp) removed. Size
fractionation can also be carried out on the LCM by selective binding to
magnetic beads, e.g., AMPure, (Agencourt). Input DNA can be assessed for
size and concentration on a BioAnalyzer 2100 (Agilent) and by dye binding
(Pico-Green, Quant-it, Invitrogen). The sequence of reactions is shown
schematically in FIG. 29 in the Library Construction Module box.
[0307]Fragment End Polishing
[0308]In one embodiment DNA nebulization generates fragments with a
preponderance of frayed ends that require filling in/blunt-ending before
further manipulations can take place (Bankier 1987). Phosphorylation of
5' hydroxyl termini is also required for subsequent ligation of adapters.
This can be accomplished through the successive activities of T4 DNA
polymerase and T4 polynucleotide kinase. Substrates are combined with
reaction buffer, BSA, ATP, dNTPs and the two enzymes in a small reaction
volume, initially 25 uL, incubated first at 12 degrees Celsius for 15
min., then at 25 degrees Celsius for 15 min. Temperature control can be
through Peltier devices mounted on the hard instrument interface.
Controls for the polishing reactions can rely on incorporation of
fluorescently labeled dNTPs, assayed using fluorescent imaging and
quantification or using radiolabeled dNTPs.
[0309]Microfluidic Bead-Based Purification
[0310]Following polishing, the fragments are purified by precipitation
onto beads. The LCM instrument can move fluids to the LCM cartridge (see
FIG. 28) to force DNA onto beads, actuate a magnet to concentrate beads
onto a wall of the purification chamber, and then wash the beads. As
needed the DNA can be eluted from the beads, the DNA can be moved to the
processing chamber A and the beads discarded, or the beads moved into
another chamber for further processing. This method can be reused
multiple times throughout the process. Column-based purifications are
thus replaced with bead-based purification. The sample preparation device
routinely purifies DNA in cartridges using magnetic SPRI beads (Agencourt
Biosciences), DNA IQ (Promega), and carboxylated beads (Invitrogen) for
DNA sequencing, forensics, and biodefense applications respectively.
Purified products can be assayed on a BioAnalyzer (Agilent) and by dye
binding (Pico-Green, Quant-it, Invitrogen).
[0311]Ligation of Adaptors
[0312]Next, adaptors are ligated to the purified DNA. The DNA in the
purification chamber can first be eluted from the beads into ligation
buffer, which is moved to the reaction chamber by pressure driven flow,
and adaptors and ligase added. The adaptors can contain nested PCR and
sequencing priming sites, blunt 3' ends and 5' overhangs; one adaptor of
each pair can have a biotin on the 5' end. Each adaptor can incorporate a
nucleotide-based `key` that serves to identify the sample and the
processing steps and a `sequencing key` to assist in base-calling.
Ligation and further selection selects for fragments with different
adapter (one with biotin, one without) on each end. At this point before
being bound to streptavidin beads the ligation products again can need to
be purified on beads in the purification chamber and the library moved
back to the processing chamber.
[0313]Ligations can be conducted with ligase such as quick ligase (New
England Biolabs), buffer and adaptors and incubated for 15 min at 25
degrees Celsius. Products can be assayed for the ligation of adaptors by
Q-PCR, using the PCR priming sites and 5' sequencing priming site for
probe. Efficiencies of ligation and recovery of target can be calculated
by comparing the amount of starting materials and yields after relevant
steps. Also, pre-binding one adaptor via a biotin-streptavidin linkage to
a paramagnetic bead will result in bead-bound fragments that can then be
subjected to a second round of ligation with the second adapter. This
approach can prevent the generation of fragments with no biotinylated
adapters and those with two biotinylated adapters, which are both lost
during processing. This could significantly improve the final yield of
template. After ligation, the products are again bead-purified.
[0314]Library Immobilization
[0315]Pre-washed streptavidin-coated beads resuspended in Library Binding
Buffer can be added from a reagent reservoir to the purified ligation
reaction products that have been moved back to the processing chamber and
incubated for 20 min with mixing at RT. The material is then bead
purified on the streptavidin bead in the purification chamber to remove
adaptor dimers.
[0316]Nick Repair
[0317]Ligation results in 3' nicks, which can be repaired by Bst DNA
polymerase (Large Fragment). Fill-in Buffer, and dNTPs, can be added
directly to the beads and incubated at 65 degrees Celsius for 30 min. The
beads are then purified in the purification chamber.
[0318]u
[0319]25 uL of premixed Melt Solution (125 mM NaOH) can be added directly
to washed beads in the purification chamber, mixed, the bead pelleted
using a magnet, and the resulting supernatant moved to the processing
chamber where 62.5 uL Neutralization Solution (0.15% acetic acid) can be
added. A second round of treating the beads with denaturant results in a
total volume of 113 uL of single stranded template. These would again be
purified before eluting in a volume of 10 uL.
[0320]Automation, upstream normalization of the input material, or using
limiting amounts of beads are various steps that can greatly aid in
uniform production and amplification of libraries, which can lead to the
elimination of the quality check at this point.
[0321]In one embodiment, continued quality assessment and functional
quantification can be performed. The quality of the SS library can be
assessed off-line, if required, using an Agilent 2100 Bioanalyzer, which
can provide the size range of fragments; yields can also be assessed
using Q-PCR, or dye binding (RiboGreen, Quant-iT, Invitrogen). The
library can further be functionally tested by forming a dilution series,
performing emulsion PCR (emPCR), and pyrosequencing to determine the
working dilution for the emPCR. Automated fragment separation can also be
incorporated into the device.
[0322]Binding to Capture Beads
[0323]The SS DNA prepared in prior steps can be annealed to controlled
pore glass (CPG) or styrene beads with bound DNA capture primers
complementary to the ends of the ligated adapters. Handling of
non-magnetic beads, such as these, can require the use of pumped
filtration technology (to avoid the use of centrifugation). Because the
reagents used can be purified of any particulates and the beads can be
pre-washed and quantified using a Coulter Counter (Beckman Coulter),
filter clogging should not be an issue.
[0324]The beads can be added to the template library, now single stranded,
and mixed to favor annealing of a single template/bead in hybridization
solution in the annealing chamber. Initially, the bead-template mixture
can be divided into aliquots for subsequent emulsion generation and
annealed by ramping from 80 degrees Celsius with holds at 10 degrees
Celsius intervals in a standard thermal cycler. Temperature-ramping
capabilities can also be incorporated into the LCM device. Resuspension
of filtrates (i.e., washed beads) can be accomplished by back washing the
filters. Hybridization of the SS library can be assessed by assaying for
unhybridized SS DNA in the supernatant by Q-PCR on aliquots before and
after bead hybridization. At this stage of processing the single stranded
template on beads can be transferred to the emPCR Production Module or
similar device for further processing.
Example 4
Coupling of a Sample Preparation Device with a Microchip-Based Sample
Cleanup and Separation
[0325]FIG. 34 and FIG. 35 show a device with a cartridge (2907) and
microchip (2901) that was designed to incorporate the Forked Injector
design, as shown in FIG. 32, a gel filling manifold (2903), and
associated components. The cartridge is fluidically connected to a
pneumatics manifold and tubing (2905). Different configurations of the
injector design, separation channel length and separation polymer were
tested. FIG. 36 show an electropherogram of an M13 T track injected and
separated on a microchip channel using the Forked Cathode injector, with
sample detection on a confocal microscope breadboard system. The sample
was injected uniformly with short and long DNA fragments represented
equally. The results show that an M13 T track DNA ladder can be uniformly
injected and single base pair resolution can be obtained out to
approximately 330 base pairs in less than 20 minutes. Higher sample
signal strengths were obtained compared to injections using a
conventional twin T design. When integrated with a detection system, the
microchip is held at a constant 50.degree. C. in order to obtain
separations with good resolution.
[0326]Using these processes, excellent results were obtained for MOVe
integrated, field amplified stacking injections of liquid samples (FIG.
37). This data was generated with all sample loading, manipulation and
injection processes carried out under software control using MOVe
microvalves. The data has been minimally processed, color corrected from
a detector that uses eight diode channels to four dye traces.
[0327]One embodiment of a microchip that combines the forked cathode with
a MOVe sample preparation device is shown in FIG. 38. This device
comprised additional processes that enable integration with the rest of
the system, i.e., the sample preparation device (1000 shown in FIG. 22),
the reaction channel (250 shown in FIG. 6), and the output of the STR
purification as described in the STR example. FIG. 38 shows a forked
cathode with MOVe fluidics and shuttle sample loading for integration
with post amplification STR purification system. The parts are:
1--Reagent input port, 2--Reagent pump head, 3--Sample input port,
4--Size Standard/eluent input port, 5--Capture valve, 6--Waste port,
7--Elution valve, 8--Sample waste port, 9--Cathode, 10--Cathode port,
11--Sample valve, 12--Sample port, and 13--Separation channel. The anode
port, which is downstream of the channel, is not shown.
[0328]The sample to be separated is introduced as a bead solution in
ethanol. This can be the purified reaction products on beads output as
described above. In one embodiment, the sample is an STR reaction. In
other embodiments, the sample can be nucleic acid fragments of different
lengths produced by other reaction chemistries including DNA sequencing
by Sanger chemistry. The solution containing the sample is flowed from
the Sample input port to the Sample waste port with the Capture valve and
other intervening valves open. The open Capture valve facilitates a
slowing of the stream flow and bead capture by a fixed magnet placed
above or below the valve. The ethanol solution is completely run through
the system followed by air yielding a relatively dry and clean bead bed,
with purified products, in the valve. At this point the valve is closed
and reopened (in coordination with other valves) to fill it eluent
solution from the associated port. For an STR analysis or other analyzes
where an internal size standard is needed, the eluent can contain a size
standard. The solution is moved between the Elution valve and the Capture
valve to facilitate mixing, ending with the solution in the Elution
valve. The Sample valve is then opened in coordination with the Elution
valve closing to "shuttle" the sample through the sample channel leaving
it filled. The sample FASS injection is carried out as previously
described. An additional noteworthy function of the device is that in one
embodiment the Reagent input port and Reagent pump are used to provide
metered STR reaction premix to the reaction channel (250 shown in FIG. 6)
after the swab extraction of DNA on the sample preparation device; in
other embodiments, the device can provide other nucleic acid reaction
reagents such as cycle sequencing mixture or provide PCR reagents to
perform a PCR amplification followed by providing cycle sequencing
reagents to perform cycle sequencing with bead-based cleanup reactions
integrated as needed. Other chemistries will be apparent to one skilled
in the art.
Example 5
Integrated Nucleic Acid Isolation, Amplification, Separation and Detection
System
[0329]A sample preparation device with cartridge(s) and thermal regulating
device can be integrated with downstream detection systems to produce a
sample-to-answer fully integrated system. The system can be fashioned
into a compact format that is compatible with laboratory, clinical, and
field operation as a benchtop or portable device, as shown in FIG. 39.
FIG. 39 shows one embodiment of a system that can extract swabs or other
materials using a five channel swab extraction assembly 800 using
cartridges (1) to purify nucleic acids from input buccal swabs, liquids,
solids, and other materials. The purified nucleic acids on beads is PCR
amplified in Thermal Cycling Module 400. In one embodiment, the samples
are bead purified in swab extraction assembly 800 using cartridges (1) to
purify the desired products onto beads. The beads are moved to Separation
and Detection Module 900 to receive the products on beads, elute the
sample and separate it by capillary electrophoresis or microchip
capillary electrophoresis or other separation methods with detection
methods such as Laser Induced Fluorescence or mass spectroscopy. For
capillary electrophoresis or microchip capillary electrophoresis, Gel
Injection Module 850 pumps separation matrix or gels or other materials
to provide the separation columns and regenerate them. In another
embodiment, the Gel Injection Module 850 could pump chromatography media
if the separation was by HPLC or other liquid chromatography methods.
Electronics and Power Supply Module 860 provides control and power
function. Pneumatics Module 870 supplies regulated air and vacuum to
operate the swab extraction assembly 800. Reagents are stored in reagent
storage 880. Reagents can be stored in solution or dehydrated or
stabilized forms such as Ready-to-Go (GE Healthcare) and lyophilized
forms.
[0330]In one embodiment, the system is configured to perform STR analysis
of buccal swabs. Buccal swabs are extracted in assembly 800 and the
extracted samples amplified in Thermal Cycling Module 400 using reagents
for STR amplification. The amplified samples are purified using nucleic
acid extractions onto beads, for example using Orapure or DNA IQ
chemistries and beads. The purified STR products on beads are then moved
to Separation and Detection Module 900 and the beads are captured and the
DNA eluted, preferably on a microchip with MOVe microvalves. The samples
are then injected preferably into a Forked Cathode Injector on a
microchip or a capillary electrophoresis capillary coupled to a microchip
and using capillary gel electrophoresis separations with gels such as
dynamic coating gels, V2E (GE Healthcare), polydimethyl acrylamide, the
POP family of matrices (Applied Biosystems), hydroxymethylcellulose,
guarin, and linear polyacrylamide. The detected products with fluorescent
labels pass a Laser Induced Fluorescent detector which detects the peaks
as they move by.
[0331]In another embodiment, the system is configured as an integrated DNA
sequencer. The sample is extracted in assembly 800 and the extracted
samples amplified in Thermal Cycling Module 400 using reagents for PCR
amplification. The samples can be whole organisms, tissues, cell,
viruses, air, liquid, or solid without limitation. The DNA extraction can
be non-specific using a bead-based purification method such as Orapure
(Agencourt) or can use hybridization or other methods to select one or
more regions from the input sample to produce a less complex sample. It
will be apparent to one skilled in the art that the USPM workflow with
IMS followed by the nucleic acid purification can also be adapted to the
sample preparation device 800 and the swab extraction replaced by many
other initial purification workflows. The PCR amplification can be of a
single region or multiplexed to target multiple regions. The amplified
PCR samples are purified using nucleic acid extractions onto beads, for
example using Orapure or DNA IQ chemistries and beads. The purified PCR
products on beads are then moved to the Thermal Cycling Module 400 and
cycle sequencing master mix added and the samples cycle sequenced. This
can be with fluorescent labels or as four sets of unlabeled primers for
label-less detection by UV or other methods. The cycle sequenced samples
are then moved to assembly 800 and bead purified to remove unwanted ions
and labels, and other material. The beads are then moved to Separation
and Detection Module 900 and the beads are captured and the DNA eluted,
preferably on a microchip with MOVe microvalves or into capillaries. The
samples are then injected preferably into a Forked Cathode Injector on a
microchip or a capillary electrophoresis capillary coupled to a microchip
and using capillary gel electrophoresis separations with gels such as
dynamic coating gels, V2E (GE Healthcare), polydimethyl acrylamide, the
POP family of matrices (Applied Biosystems)hydroxymethylcellulose,
guarin, and linear polyacrylamide. The detected products with fluorescent
labels pass a Laser Induced Fluorescent detector which detects the peaks
as they move by.
[0332]In other embodiments the protein, carbohydrate, or other assays are
performed and the detection is by mass spectrometry, imaging, HPLC, GC,
or other analytic methods well known to one skilled in the art.
[0333]For DNA, the processed sample can be amplified by PCR, rolling
circle, branched DNA, EXPAR, and other DNA amplification methods well
known to one skilled in the art or analyzed by mass spectroscopy or
single molecule detection methods. RNA can be processed by Reverse
Transcriptase real time-PCR, or samples prepared for DNA microarrays, or
other analytical methods. Real time or end point analyzes can be
performed with the apparatus. For proteins, assays can be performed in
the cartridge including enzymatic assays, sandwich immunoassays, antibody
precipitation, protein digestion, protein and peptide labeling, and other
commonly used protein analysis methods. Similarly, other cellular
components or chemicals can be extracted or purified using standard
methods in the apparatus. Molecular biology methods are readily adapted
to the apparatus. Samples can be completely analyzed on the apparatus in
a single cartridge, moved to a separate cartridge, or analyzed or further
processed in a separate instrument comprising a capillary electrophoresis
system or microchip capillary electrophoresis; multidimensional gel and
capillary electrophoresis; mass spectroscopy, multidimensional mass
spectroscopy with HPLC, ICP, Raman spectroscopy, particle, nanoparticles,
and bead based detection, imaging, comprising fluorescence, IR, optical,
or any other analytical systems well know to one in the art.
[0334]The integration of a complete sample-to-answer instrument
incorporating the cartridge to prepare DNA samples from many inputs and
sample types and a microchip-based capillary electrophoresis device for
separation of DNA fragments is taught for DNA sequencing, fragment
sizing, and forensics.
Example 6
Device with Four Processing Channels
[0335]A microchip or microfluidic microchip can be used to amplify mRNA,
concentrate nucleic acids on magnetic beads and inject purified samples
into electrophoretic separation capillaries. As shown in FIG. 45 and FIG.
46, a microchip (505) can be interfaced with a cartridge (503) and a
pneumatic manifold (507). FIG. 45 shows an expanded view of the
microchip, cartridge, and pneumatic manifold. FIG. 46 shows a view of the
cartridge interfaced with the microchip, which is interfaced with the
pneumatic manifold. The cartridge can completely cover the surface of the
microchip. Additionally, a block (501) has holes (509) that help to hold
for incubation materials delivered to or from ports (511) of the
cartridge (503). The block can be a heat block or a temperature
controlling block. The holes (509) can be used to hold to hold pipette
tips or be used as a large volume reactor or processor. The block (509)
can be heated or cooled to control the temperature of material being
delivered to cartridge and microchip or removed from the cartridge and
microchip. The block can be in thermal contact with the cartridge. The
ports of the cartridge can lead to reservoirs that are fluidically
connected to ports that mate with ports (515) on the microchip (505). The
microchip (505) can have pneumatic line ports (519) that mate with ports
(517) of the pneumatic manifold. The ports of the pneumatic manifold can
have o-ring gaskets that seal the pneumatic manifold to the microchip,
allowing for high and low pressures to be delivered without leaking or
with a reduced loss of pressure or vacuum. The cartridge, microchip, and
pneumatic manifold can be held together using bolts or other securing
objects that pass through openings (513, 501) of the cartridge and the
pneumatic manifold.
[0336]A diagram of the Chip A microchip is shown in FIG. 47. The microchip
comprises three layers: (i) a top fluidics layer (e.g., glass) carrying
fluidic channels and wells, (ii) a bottom pneumatics layer (e.g., glass)
carrying pneumatic channels and wells, and (iii) a middle flexible
membrane, (e.g., 250 um thick, PDMS layer) (not shown). The PDMS membrane
can be featureless. The PDMS membrane can deflect in response to positive
or negative pressure applied to localized areas defined by the pneumatic
channel system (dashed lines in FIG. 47). Pneumatic and fluidic channel
etch depths are typically 50 um and can be designed to offer minimal
hydraulic resistance. Valves in the microfluidic system can include pump
valves. Pump valves can be larger than other valves, depending on the
desired pump capacity, and can lack a valve seat. Removal of the valve
seat can increase the pumping capacity, or the volume of fluid that is
pumped per pump stroke. Other valves can be smaller, and have a valve
seat that allows them to close firmly. Such reduced volume on/off valves
can reduce the overall void space within the microfluidic microchip.
Inlet and outlet valves can be such on/off valves.
[0337]As shown in FIG. 47, the microchip has four identical processing
channels, each of which can control reagent flows for off-microchip or
on-microchip magnetic-bead-based nucleic acid concentration and capillary
electrophoresis sample injection. The four processing channels are fed by
a common "reagent rail" which can select input reagents from four input
wells (the fifth well can be used as a waste port). Individual samples
can be fed into each processing channel from channel-specific sample
wells, and can be processed in parallel (the microchip shown is a 4-plex
processing device). Each processing channel can have a 0.8 .mu.L pump,
sample input well, two output wells, and a waste well. Beads, such as
magnetic beads, can be captured in any of the wells, e.g. one or both of
the output wells. This output well can interface with the cartridge or
fluidic manifold.
[0338]A photograph of the Chip A microchip, is shown in FIG. 48. The
microchip can be mounted between a top fluidic manifold, mating fluid
reservoirs to wells on the top surface of the microchip, and a bottom
pneumatic manifold, mating pneumatic control lines to wells on the bottom
surface of the microchip via o-ring seals. Microchip valves and pumps can
be actuated by a pneumatic control system driven by computer scripts,
such as DevLink scripts, or other software. The system can supply
positive pressure (approximately +10 psi) to close valves, and/or
negative pressure (approximately -20 psi or vacuum) to open them. The
same pneumatic system can operate microchip pumps, with negative pressure
acting to fill the pump bodies (on the fluidic channel side of an
elastomeric layer), and positive pressure acting to empty them. As
described herein, pumping action depends on the coordinated actions of
pumps and flanking inlet and outlet valves.
Example 7
mRNA Amplification Using Device with Four Processing Channels
[0339]Chip A was used to perform the first, reverse transcription,
reaction of the Eberwine protocol. Effective mixing and incubation
methods were developed.
[0340]In order to provide temperature control for the approximately 10 ul
reaction, a simple heated aluminum block (509), carrying eight 200 ul
pipette tips, was fabricated and mated to the fluidic manifold as shown
in FIG. 45, FIG. 46, and FIG. 49. Each pipette tip connected to a
microchip output. In the experiment, only 4 tips, connected to microchip
Output-1 wells (as indicated in FIG. 47), were actually used. Heating
(50.degree. C.) was accomplished with a thin-film heater attached to the
outer surface of the block with adhesive. A thermocouple was inserted
into the center of the block, and the heater was controlled with a
DevLink PID control loop.
[0341]For mixing, a DevLink script was developed to mix samples and a
reagent in a 1:1 ratio by alternately pumping approximately 0.6 ul from
each respective reservoir into a pipette tip mated to Output-1.
Experiments with food dye confirmed that alternate pumping effectively
mixed the two components in the tip.
[0342]To perform the reaction, a mixture of total RNA and T7
Promoter-Primer (in water) was pipetted into sample well reservoirs, and
a two-fold concentrated RT Mix, containing Superscript III reverse
transcriptase, was pipetted into a reagent reservoir. After 15 ul had
been loaded into the tips (12 pump cycles), the script terminated, and
the reactions continued incubating for 15 minutes at 50.degree. C. At
this point the tips were removed, emptied into 0.2 ml PCR tubes, and the
reactions terminated by incubation at 85.degree. C. for 5 minutes in a
thermocycler.
[0343]Positive control reactions were treated identically, except that
these reactions were performed entirely at the bench and incubated 15 min
at 50.degree. C. in a thermocycler. Negative control reactions were mixed
(at the bench) and immediately terminated by incubation for 5 min at
85.degree. C.
[0344]Reactions were analyzed by TaqMan real-time quantitative PCR using a
Gusb primer and probe set (ABI). The results are shown in FIG. 50 for 15
.mu.L reactions containing approximately 500 ng total RNA (Rat Liver) and
10 U/.mu.L Superscript III RT. Results from channels 1-4 are shown with
results on the performed entirely at the bench indicated by iK. In FIG.
50, the pair of bars shown for each of channels 1, 2, 3, 4, and iK
represent replicate reactions. The results showed that microchip and
bench reactions were identical in their yield of first-strand Gusb cDNA.
Both reactions produced Ct's between 26 and 27. Negative control
reactions produced Ct>35 (data not shown).
Example 8
Device with Bead Clean-Up Chambers
[0345]A microchip or microfluidic microchip can be used to amplify mRNA,
and to concentrate and purify nucleic acids on magnetic beads. FIG. 51
shows an expanded view of a device that has a microchip 1307 that can be
interfaced with a cartridge made of two pieces 1313, 1315 and a pneumatic
manifold 1301. The cartridge is made of a first piece that has serpentine
channels 1311, wells, reservoirs, and chambers, and a second piece (1315)
that has wells and chambers. The serpentine channels can be used to
increase heat transfer between the heat distributing piece and a fluid
contained within the serpentine channels. The second piece and first
piece can be bonded together such that the serpentine channels are
enclosed on a top side. The cartridge can be overlayed or in thermal
contact with a heat distributing piece (1317) that distributes heat from
thermal control blocks (1323, 1321). The thermal control blocks can be
thermo electric coolers (TECs or Peltier devices), thin-film heaters, or
other thermal control devices. The heat distributing piece and heat
blocks may or may not be bonded or secured to the cartridge. Screws,
bolts, and/or hinges may facilitate the securing of the heating
distributing piece and/or heat blocks to the cartridge. FIG. 52 shows a
view of the cartridge interfaced with the microchip, which is interfaced
with the pneumatic manifold. The pneumatic block may have annular spaces
(1305, 1309) for bolts and/or screws and ports (1303) that interface
between pneumatic lines and the pneumatic layer of the microfluidic
microchip. Additional views of the pneumatic layer are shown in FIG. 53,
FIG. 54, FIG. 55, and FIG. 56. FIG. 53 and FIG. 55 show views with dashed
lines indicating edges that are hidden from view. FIG. 53 and FIG. 54
show three dimensional views of the pneumatic layer. FIG. 55 and FIG. 56
show top views of the pneumatic layer.
[0346]FIG. 57 and FIG. 58 show diagrams of a microfluidic microchip, the
Chip B microchip, with bead clean-up chambers. Referring to FIG. 58, the
microchip has four main sections: Reagent Rail, Bead Rail, Processor 1,
and Processor 2. The two rails and the two processors have mirrored
geometries. The microchip is configured so that either reagent rail may
feed either processor. Access to the processors is controlled by valves
Vr and Vb for the top processor and by valves Vrb and Vbb for the bottom
processor. During reagent processing and enzymatic reactions of the top
processor, Vr is opened and Vb is closed. During reagent processing and
enzymatic reactions of the bottom processor, Vrb is opened and Vbb is
closed. During clean-up, the reverse applies, that is, for the top
processor Vr is closed and Vb is opened and for the bottom processor Vrb
is closed and Vbb opened. It can be seen that the top and bottom
processor can operate either in parallel or separately. Reagent and Bead
Rail design closely follows the Chip A design. Each rail can access four
different reagents (R1-4 and B1-4), via valves Vr1-4 and Vb1-4
respectively, and each rail has waste wells (RW and BW), accessed by
valves Vrw and Vbw, respectively. Each processor has a sample input well
(S), two output wells (Oa, Ob), and a bead side channel accessed by
valves Vs, Voa, Vob, Vbs respectively. The bead side channel has a bead
reservoir (R), and two valves (Vw and Ve) accessing waste (W) and elution
(E) wells, respectively. Pneumatic lines and ports for control of the
valves are shown as dashed in FIG. 57.
[0347]For purposes of explanation below, it is assumed that Processor 1
and Processor 2 are operated identically in parallel, and that Chip B is
a duplex device, processing two samples simultaneously. For clarity, the
operation of only the top processor is detailed. However, non-parallel
operation is also possible. It is also assumed that wells Oa and Ob are
connected to appropriate capacity reservoirs in a fluidic manifold or
tubing. Reservoirs can be pipette tips, a reservoir in a cartridge, or
connected by tubing to larger volumes The microfluidic microchip can have
75 .mu.m channel depth, 250 .mu.m (final) fluid channel width, and 0.6
.mu.l (estimated) pumping stroke volume.
[0348]Referring to FIG. 58, a reaction comprising Reagent 1 and Sample may
be assembled in well Oa by alternate 4-cycle pumping (A, B, C, D). Assume
all valves are initially closed. In cycle A, valves Vr1 and Vr open,
allowing pump P to draw Reagent 1 from well R1 with a down-stroke
(negative pressure applied to pump P to open the valve). In cycle B,
valves Vr1 and Vr close and valve Voa opens, allowing pump P to expel its
contents (from R1 in this example) into well Oa with an up-stroke
(positive pressure applied to pump P to close it). In cycle C, valve Vs
opens and valve Voa closes, allowing pump P to draw Sample from well S
with a down-stroke. In cycle D, valve Vs closes and Voa opens, allowing
pump P to expel its contents into well Oa with an up-stroke. These four
cycles are repeated until a sufficient volume has been pushed into Oa.
The mixing ratio between Sample and Reagent 1 is determined by the ratio
of cycles AB:CD. In the process described above, the mixing ratio is 1:1,
but it can in principle be any value. Finally, similar procedures can be
used to mix any of the reagents (R1-4) with sample S, by substituting the
appropriate valve for Vr1. Referring to FIG. 58, in 4-cycle pumping, the
fluid can be pumped in a first direction from a first source well to a
space within a pumping valve in the first step. In the second step, the
fluid can be pumped in a direction opposite to the first direction by
moving the fluid from the pumping valve to a mixing well. The third and
fourth steps can be repeated with a second source well instead of the
first source well. The pumping in opposite directions to obtain mixing in
the mixing well can be a result of having the source well, mixing well,
and pumping valve positioned along a channel such that the pumping valve
is not located between the source well and the mixing well. This
configuration can reduce the dead space within the microfluidic
microchip, improve mixing, or improve uniformity of reagent and sample
handling. As well, this configuration can allow for a central pump to
move liquid between many different wells on a microfluidic microchip
through the opening and closing of appropriate valves.
[0349]The valves shown in FIG. 57 and FIG. 58 and any other valve shown
herein sometimes are placed at T-shaped junctions. The valves can close
off flow from one channel of the T to the other two channels leading into
the T, while continuing to allow flow between the other two channels. For
example, closing valve Voa prevents fluid from flowing from pump P to Oa,
but does not prevent fluid from flowing from pump P to S if valve Vs is
open. Alternatively, a valve can obstruct flow between all channels
leading into the T. The same can be applied to valves that are placed at
junctions of 4, 5, 6, or more channels. The valves can also be replaced
by valves that are only in the reagent or bead channel as needed.
Example 9
mRNA Amplification Using Device with Bead Clean-Up Chambers
[0350]As described above, the Eberwine mRNA amplification procedure is a
cascade of three binary additions. To execute the Eberwine sequence, R1
contains RT Mix, R2 contains 2S (second-strand) Mix, and R3 contains T7
Mix, as shown in FIG. 58. A two-fold (2.times.) volume of 2S Mix can be
added to the RT reaction, and a one-fold volume of T7 Mix can be added to
the 2S reaction, as shown in FIG. 44. This requires a 2:1 pumping ratio
(AB:CD) for the 2S Mix addition, and a 1:1 ratio for the T7 Mix addition.
[0351]The first (RT) reaction with a 1:1 mixture of total RNA+Primer, from
well S, and 2.times.RT Mix, from well R1, can be formed using the methods
described herein. After an appropriate incubation period, the
second-strand reaction may be assembled in well Ob by drawing from well
Oa (rather than well S), and drawing from well R2 (rather than from well
R1). A four-cycle pumping scheme (A, B, C, D) similar to that described
in Example 8 can be used. In cycle A, Vr2 opens rather than Vr1; in cycle
B, Vob opens rather than Voa; in cycle C, Voa opens rather than Vs; and
in cycle D, Vob opens rather than Voa. To obtain the required 2:1 mixing
ratio, two cycles can draw from R2 for every cycle drawing from Oa.
[0352]After another appropriate incubation period, the third (T7) reaction
may be assembled in well Oa with a similar process (drawing from R3 and
Ob, 1:1 ratio). Thus the final T7 reaction can reside in Oa. After an
appropriate incubation period, aRNA can be ready for purification.
[0353]Purification involves operation of the Bead Rail rather than the
Reagent Rail. Thus, during this phase of microchip operation, valve Vr
remains closed and Vb can open.
[0354]To purify aRNA, reservoir R must first be loaded with magnetic
beads. This may be accomplished with a 2-cycle procedure, similar to that
of cycles A and B of Example 8, except that input to pump P can be via
valves Vb4 and Vb (cycle A), and output from pump P can be via valves Vbs
and Vw (cycle B). This sequence can draw bead slurry from well B4 into
pump P, and expel bead slurry from pump P through reservoir R into waste
well W. As the slurry passes through reservoir R, beads can be captured
by a magnet placed below reservoir R.
[0355]Before aRNA (in well Oa) can be captured, it must be mixed with
Binding Buffer. This can be accomplished with another 4-cycle procedure,
similar to that in Example 8, except that Binding Buffer can be drawn
from well B1 in the Bead Rail, and the mixture can accumulate in well Ob.
[0356]aRNA in well Ob can then be captured by beads in reservoir R by
pumping the contents of well Ob through reservoir R out into waste well
W. This can be accomplished with a 2-cycle procedure in which pump P is
filled via valve Vob (cycle A) and emptied via valves Vbs and Vw (cycle
B).
[0357]Loaded beads can then be washed with ethanol pumped from well B2.
This can be accomplished with a 2-cycle procedure in which pump P is
filled via valves Vb2 and Vb (cycle A) and emptied via valves Vbs and Vw
(cycle B). After ethanol from well B2 has been exhausted, pumping can
continue to draw air over the beads to dry them.
[0358]Finally, aRNA can be eluted from the beads into well E by pumping
water through reservoir R with a 2-cycle procedure in which pump P is
filled via valves Vb3 and Vb (cycle A) and emptied via valves Vbs and Ve
(cycle B).
Example 10
Short RNA Amplification Using Device with Real-Time PCR Detection
[0359]MicroRNA (miRNA) are short (19-25 nucleotide) single-stranded RNAs
that are produced by processing larger RNAs, while siRNA are short (20-25
nucleotide) double-stranded RNAs that are also produced by processing
larger RNAs. miRNAs have been implicated in regulating translation of
mRNA while siRNAs can silence or activate transcription of genes. Both
miRNA and siRNA, collectively small RNAs, can be assayed using the
devices described herein. To assay either small RNA, the device in FIG.
58 would be reconfigured with 1) R3 containing a mixture to polyadenylate
the short RNA, 2) R4 containing real-time PCR primers and real-time
master mix, and 3) the RT mixture in R1 can contain a polyT sequence with
a 5' sequence for real-time PCR amplification instead of a T7 promoter.
The reaction would proceed as described in Example 9 except first a polyA
tail would be added to the small RNAs to produce polyadenylated small
RNAs using R3 as the reagent source. The reverse transcription and second
strand synthesis can operate as described in Example 9. The final step of
T7 transcription is then replaced by mixing the real time PCR primers and
master mix from R4 with the second strand product. The real time PCR
primers are then amplified using PCR with real time detection. The
amplification can occur off-microchip or a detector and thermal cycling
can be incorporated on the microchip or in heating block (509). Real time
PCR on microchips was previously described, e.g. Jovanovich, S., I.
Blaga, and D. Rank. Microfluidic Devices. US Patent Publication No.
2007/0248958 and PCT Publication No. WO/2006/032044, which are hereby
incorporated by reference. It will be obvious to one skilled in the art
that other mRNAs can be processed as described in this example by
omitting the polyadenylation step.
[0360]While preferred embodiments of the present invention have been shown
and described herein, it will be obvious to those skilled in the art that
such embodiments are provided by way of example only. Numerous
variations, changes, and substitutions will now occur to those skilled in
the art without departing from the invention. For example, any MOVe
valve, pump, router, or other MOVe device described herein can be
replaced with any pneumatically actuated valve, pump router or other
device. It should be understood that various alternatives to the
embodiments of the invention described herein can be employed in
practicing the invention. It is intended that the following claims define
the scope of the invention and that methods and structures within the
scope of these claims and their equivalents be covered thereby.
* * * * *