Adsorption of IgG and BSA on Two Chromatographic Resins—Poly(ethylenimine)-4FF Resin and Tetrapeptide-poly(ethylenimine)-4FF Resin

Abstract

Poly(ethylenimine) (PEI) as a long flexible chain has been well used in protein chromatography with the advantages of high spatial utilization and “chain delivery” effect. In this work, two resins, i.e., poly(ethylenimine)-4FF resin (PEI-4FF resin) and Ac-YFRH-PEI-4FF resin by grafting tetrapeptide to PEI-4FF resin, were prepared for the protein adsorption and chromatographic separation. The pH-dependent adsorption properties of PEI-4FF resin and Ac-YFRH-PEI-4FF resin were discovered by getting the data of adsorption capacities of bovine serum albumin (BSA) and immunoglobulin G (IgG) under different pH conditions and buffer systems. The results showed high binding capacities of BSA on PEI-4FF resins across a range of pH values (5.0–8.9) with almost very little adsorption of IgG over a pH range from 5.0 to 8.0, indicating that IgG could be separated by flow-through method using PEI-4FF resin. Since PEI has the advantage of having many flexible branched chains and Ac-YFRH (Ac-Try-Phe-Arg-His) as a peptide l...