Abstract
Post-translational modifications (PTMs) must be characterized and controlled for effective and safe biotherapeutic development, such as monoclonal antibody treatments. Many PTMs are polar by their nature, including glycosylation, deamidation, and oxidation. These types of polar modifications lend themselves to analysis via hydrophilic interaction liquid chromatography (HILIC) since they can be better resolved than with reversed-phase chromatography. Examples of glycosylation, deamidation, and oxidation of different mAbs will be demonstrated using LCMS under HILIC conditions.