Antibody-drug conjugate characterization by chromatographic and electrophoretic techniques

Due to the inherent structure complexity and component heterogeneity of antibody drug conjugates (ADCs), separation technologies play a critical role in their characterization. In this review, we focus on chromatographic and electrophoretic approaches used to characterize ADCs with respect to drug-to-antibody ratio, drug distribution and conjugation sites, free small molecule drugs, charge variants, aggregates and fragments, etc. Chromatographic techniques including reversed-phase, ion exchange, size exclusion, hydrophobic interaction, two-dimensional liquid chromatography, and gas chromatography as well as capillary electrophoretic techniques including capillary electrophoresis sodium dodecyl sulfate, capillary zone electrophoresis and capillary isoelectric focusing are reviewed for their applications in the characterization of ADCs.