LC–MS/MS has gained momentum as an orthogonal approach to ELISA for host-cell protein (HCP) analysis. LC–MS/MS can identify and quantify individual HCPs, and help ensure that no HCPs evade detection above a reportable limit.
A new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but with short digestion times and time-course elements to minimize and monitor deamidation–isomerization, respectively, enabling a more accurate assessment of potential CDR sequence liabilities.