Application of arginine as an efficient eluent in cation exchange chromatographic purification of a PEGylated peptide

A cation exchange chromatographic purification process step was developed for the purification of human PEGylated PYY 3–36 from the PEGylation reaction mixture. In this publication we describe experiments carried out to evaluate the chromatographic performance of arginine chloride as an effective cation exchange chromatography eluent. Using arginine we obtained improved recovery and resolution during chromatographic purification of a peptide PEGylation reaction mixture. The chromatographic elution performance of arginine was compared to other cationic amino acids and sodium chloride. Arginine provided higher yield and better resolution of product from other process impurities. The process was successfully scaled up to produce clinical supplies. The basis for improvement in process performance with arginine was characterized by examining the effect of buffer and concentration of the PEGylated peptide on hydrodynamic volume of the molecule in solution. These results were used to predict the behavior of the molecule in the chromatography process. The enhanced chromatographic performance could be attributed to changes in molecular size with concentration, higher eluent strength of arginine, and resulting changes in mass transfer resistance.