Affinity cell separations: Problems and prospects

The use of biospecific interactions for the separation and recovery of biomolecules is widely established, but developments in affinity-based separations for cell fractionation have been slow. Many of the problems encountered result from applying techniques developed for molecular systems to cell separation with only minor modification to the conditions. This approach tends to ignore, or at least trivialize, the problems that arise from the heterogeneous nature of a cell suspension and the implications of cooperativity that can occur with multivalent interactions. This article considers how alternative protocols might be used to develop more attractive cell-separation processes.