Cation- exchange column Key:Large net positive charge Net positive charge O Net negative charge Large net negative charge Polymer beads with negatively charged functional groups 平0 Protein mixture is added to column containing cation exchangers. Proteins move through the column at rates determined by their net charge at the pH being used.With cation exchangers,proteins with a more negative net charge 12345 move faster and elute earlier. (a) Cation￾exchange column