Additional responsibilities include but are not limited to method development for identity, purity, aggregation status, charge isoforms, and potency using chromatography (including SEC, RP-HPLC, IEX, HIC, affinity, etc.), electrophoresis (including SDS-PAGE, Western blotting, IEF, and cIEF), and other protein chemistry tools. MS analysis of intact proteins and fragments generated by various enzyme digestion; peptide mapping analysis by LC-MS for protein amino acid confirmation and relative qualification of post-translational modifications.