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Affinity Processing of Cell-Containing Feeds Using
Monolithic Macroporous Hydrogels, Cryogels
Igor Yu. Galaev and Bo Mattiasson
Summary
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 μm) 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.
Key Words: Monolithic macroporous hydrogel; cryogel; cell separation; lymphocyte
fractionation; protein A; Immobilized Metal Affinity Chromatography; cell labeling.
1. Introduction
A variety of polymeric gels are used at present in different areas of
biotechnology as chromatographic materials, carriers for the immobilization
of molecules and cells, matrices for electrophoresis and immunoanalysis, as a
gel basis for solid cultural media. Polymer gels enable us to solve numerous
technical problems in biotechnology and biomedicine; however, new, often
contradictory requirements for the gels are permanently emerging and stimulate
the development and the commercialization of new gel materials for biological
applications. One of the new types of polymer gels with considerable potential
From: Methods in Molecular Biology, vol. 421: Affinity Chromatography: Methods and Protocols, Second Edition
Edited by: M. Zachariou © Humana Press, Totowa, NJ
247