Affinity processing of cell-containing feeds using monolithic macroporous hydrogels, cryogels.

Monolithic macroporous hydrogels, "cryogels," are produced by polymerization in a partially frozen state when the ice crystals perform as a porogen. Cryogels have a unique combination of properties: (i) large (10-100 microm) pores; (ii) minimal non-specific interactions due to the hydrophilic nature of the polymers; (iii) porosities exceeding 80-90%; (iv) good mechanical stability. These properties of cryogels allow for their application for direct capture of extracellularly expressed histidine-tagged protein from the fermentation broth and separation of different cell types.