Purification of Monoclonal Antibodies Using a z2 Membrane Chromatography (z2MC) Module

Monoclonal antibodies (mAbs) comprise the largest category of biopharmaceuticals. Protein-A affinity chromatography is the standard method by which mAbs are purified. Protein-A resins are prohibitively expensive and the separation process involves mAb elution under acidic pH conditions, which could potentially destabilize the protein and promote its aggregation. Moreover, the protein-A ligand cannot distinguish between mAb charge variants. Also, aggregated forms of the mAb can bind to protein-A and therefore any aggregates present in the cell culture supernatant is co-eluted with the mAb. Hence, an alternative to protein-A based separation would be desirable. In this study, we examine mAb purification using two different types of chromatographic devices having equivalent volume: resin based (Capto S ImpAct) cation exchange chromatography column, and cation exchange z² membrane chromatography or z²MC module, a novel separation device designed and developed within our group. The z²MC device addressed some of the problems associated with the resin-based column. For example, the product obtained with the z²MC device was purer than that obtained with resin based cation exchange chromatography and the separation process was significantly faster. In this presentation we highlight the advantages of using the z²MC module for high-resolution protein separations.