Surface Modification of Cellulose Membranes To Prepare a High-Capacity Membrane Adsorber for Monoclonal Antibody Purification via Hydrophobic Charge-Induction Chromatography

Hydrophobic charge-induction chromatography (HCIC) has emerged as an efficient method for antibody purification, but traditional packed-bed chromatography continues to suffer from high pressure drop and low transport efficiency. A versatile surface modification method is proposed to prepare HCIC membrane adsorbers. We first modified a commercial regenerated cellulose (RC) membrane by the cationic ring-opening polymerization (CROP) of diethylene glycol diglycidyl ether (DEGDE), producing the RC-g-PDEGDE membrane, which was then modified by the ring-opening reaction of an epoxy group with a sulfydryl group in four mercaptoheterocyclic ligands. Bovine serum albumin (BSA) and human immunoglobulin G (IgG) were used as model contaminant and antibody, respectively. The highest ligand density achieved is 370 mmol/L, and the static and dynamic adsorption capacities of IgG reached 195 and 65 mg/mL, respectively. The high dynamic capacity and IgG recovery (96%) are believed to benefit from the branched structure of DEGDE and convective transport in membrane pores.