Cryogels for Biotechnological Applications

Cryogels are formed in a semifrozen state when the solvent is frozen, but solutes are still soluble. The ice crystals are porogens and, upon thawing the system, pores appear where the frozen solvent was found earlier. Such gels have large pores, are elastic, and offer interesting opportunities in biotechnology. Cryogels with their large pores can meet demands that traditional chromatographic media cannot. This also opens up opportunities for the separation of cells because upon passage through the gel cells may interact with specific groups on the pore walls, thereby becoming retarded and/or captured. A range of applications have been studied: isolation of microbial cells, capturing of cancer cells, and use of cryogels as matrices for immobilized cell reactors. Furthermore, the robustness of the gels allows new applications, for example in environmental separation.