In the purification of monoclonal antibodies, the separation of monomers from product-related impurities is a major challenge. Here, we highlight the importance of screening various media to determine the optimal one for an efficient purification process.
The molecule of interest in this present study, mAb S, was harvested from Chinese hamster ovary (CHO) cell culture. Typically, a Protein A affinity chromatography eluate contains a mixture of mAb S monomers (~75%) and aggregates (dimers and other oligomers, ~25%). We separated the mAb S monomers from the aggregates using three mixedmode chromatography media, CHT, Capto adhere, and Capto adhere ImpRes, which have all been extensively researched for their applications in mAb aggregate clearance (Gagnon 2009). We compared the purity and recovery of monomeric mAb S purified with these chromatography media. Our results underscore the importance of screening multiple media to develop an efficient downstream production process with the highest possible target purity and recovery.