ANALYTICAL-SCALE AND PROCESS-SCALE CELL-SEPARATION WITH BIORECEPTOR FERROFLUIDS AND HIGH-GRADIENT MAGNETIC SEPARATION

The development of small colloidal magnetic particles (< 0.1u) and their application to cell separations via high gradient magnetic methods is reviewed. An analysis of the properties of these particles contrasted to large magnetic particles (1-5u) argues for the superiority of the former even though their use has been plagued by non-specific binding issues and the use of crude high gradient magnetic separators. The development of a BioReceptor (antibody, enzyme, lectin) coated Ferrofluid and two novel high gradient magnetic separators are described. Both separators can be used for analytical scale cell separations (200 - 300 ul volumes) and one of them can easily be adapted for process scale separations. Performance data on separations done in simple and complex matrices is given.