In their recently published paper Isolation and characterization of therapeutic antibody charge variants using cation exchange displacement chromatography, research scientists Taylor Zhang, Justin Bourret and Tony Cano state "The advent of quality by design (QbD) in the biotechnology industry has increased the need for the isolation and enrichment of specific variants for biotherapeutic products ." MAb variants may form during any part of the antibody manufacturing process and their identification and/or isolation is critical as any of them can potentially affect the efficacy and safety of the therapeutic, the authors point out and continue that although the isolation and analysis of specific variants is a common requirement and "essential for assessment of biophysical and biochemical properties such as in vitro (potency and binding) and in vivo (toxicity, pharmacokinetic, immunogenicity) activity," their characterization is challenging due to the fact that most charge variants exist only at trace levels. The scientists were able to more efficiently isolate mAb charge variants and increase thoughput 10x by supplementing their mAb characterization toolkit with displacement chromatography, "a powerful but unterutilized tool in the process development and characterization of complex biological therapeutics" .
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