Figure 1.
Cation-Exchange HPLC of XOMA 3AB Antibodies. The three XOMA 3AB reference antibodies (Ab-A, Ab-B, and Ab-C) display multiple acidic and basic isoforms typical of recombinant monoclonal antibody drug products. The force-oxidized samples of each of these antibodies exhibit broad peak profiles indicating underlying structural heterogeneity. Anion-exchange HPLC (Figure 2) was evaluated as an orthogonal charge-based technique to better characterize the potential modifications.