Capillary electrophoresis separation of monoclonal antibody isoforms using a neutral capillary

Biotherapeutic proteins, such as monoclonal antibodies (mAbs), are feasible alternatives for the treatment of chronic-degenerative diseases. The biological activity of these proteins depends on their physicochemical properties. The use of high-performance techniques like chromatography and capillary electrophoresis has been described for the analysis of physicochemical heterogeneity of mAbs. Nowadays, capillary zone electrophoresis (CZE) technique constitutes one of the most resolutive and sensitive assays for the analysis of biomolecules. Besides, the electro-driven separation in CZE is governed by extensive properties of matter and offers the advantage of analyzing proteins close to their native state. However, the successful implementation of this technique for routine analysis depends on the skills of the analyst at the critical steps during sample and system preparation. The purpose of this tutorial is to detail the steps to succeed in the CZE analysis of mAbs. Further, this protocol can be used for the development and improvement of skills of the personnel involved in protein analytical chemistry laboratories.