The invention features a method for inactivating parasites in biological compositions. The method includes contacting the biological composition with an aziridino compound under parasite inactivating conditions.

Methods and compositions for the inactivation and removal of contaminants of a biological composition are disclosed. The methods include the steps of: (a) contacting the biological composition with an inactivating agent including an aziridino moiety, such as ethyleneimine, an oligomer of ethyleneimine, or a haloderivative salt of either ethyleneimine or an oligomer of ethyleneimine, where a portion of the agent reacts with and inactivates the contaminant, and a portion of the agent remains unreacted; (b) contacting the product of step (a) with a lipophilic quenching agent including at least one quenching moiety attached to a lipophilic moiety, under conditions and for a time sufficient to allow the unreacted agent to bond covalently to the quenching moiety; and (c) separating the lipophilic quenching agent and the quenched inactivating agent from the biological composition.

The invention provides a composition of greater than 90% pure ethyleneimine dimer and a method of synthesizing the same. This method of synthesis provides several advantages over previous methods: (1) The starting compounds are all relatively inexpensive; (2) the yield of product is greater than 20% of the theoretical yield; and (3) the steps of synthesis are easy, inexpensive and amenable to large-scale production. All of these advantages allow for less expensive production of ethyleneimine dimer.

Methods of inactivating contaminants of a biological matrix are disclosed. The methods include the steps of: (a) contacting a biological matrix with an inactivating agent including an aziridino moiety, where a portion of the agent reacts with and inactivates the contaminant, and a portion of the agent remains unreacted; (b) contacting the product of step (a) with a solid support including at least 1 quenching moiety attached to the solid support through covalent bonds, under conditions and for a time sufficient to allow the unreacted agent to bond covalently to the quenching moiety; and (c) separating the solid support and the unreacted agent from the biological matrix, where the unreacted agent is attached to the solid support through covalent bonds.