Insights from capillary electrophoresis approaches for characterization of monoclonal antibodies and antibody drug conjugates in the period 2016-2018.

Monoclonal antibodies (mAbs) and their related products as antibody-drug-conjugates (ADCs) or biosimilars represent a constantly growing class of molecules therapeutic proteins used as treatment against numerous diseases. These compounds can undergo several modifications which could alter the efficiency of treatments. In this context, several analytical methods were designed to deliver a comprehensive structural characterization and guarantee the quality of biotherapeutics. Capillary electrophoresis (CE) is considered today as a major technique for the analysis of biotherapeutics due to benefic characteristics as high resolution separation and miniaturized format. Different CE modes have been developed to characterize mAbs at different levels such as capillary gel electrophoresis (CGE), capillary isoelectric focusing (cIEF), and capillary zone electrophoresis (CZE). Recent developments in CE-mass spectrometry (MS) coupling assessed this technology as a promising tool to obtain high level structural characterization of biopharmaceuticals. Moreover, upcoming techniques such as 2D CE-MS and microfluidic systems are now emerging to offer new possibilities beyond actual limits. This review will be dedicated to discuss the state-of-the-art CE-based methods for the characterization of mAbs and ADCs in the period 2016-2018.