Surface Functionalization of Electrospun Cellulose Nanofiber‐Based <scp>HCIC</scp> Membrane Adsorber and Impact on Protein Binding Capacity

ABSTRACT Hydrophobic charge‐induced chromatography (HCIC) membrane adsorbers are cost‐effective for IgG separation but have limited adsorption capacity. Based on the nanofiber membrane, an HCIC nanofiber membrane adsorber with a high specific surface area was prepared by gel modification of the fiber surface. The regenerated cellulose (RC) nanofiber membrane obtained by electrospinning, thermal crosslinking, and deacetylation reaction was modified via cationic ring‐opening polymerization (CROP) of polyethylene glycol diglycidyl ether (PEGDE), followed by epoxy ring‐opening with 2‐mercaptobenzimidazole (MBI) to prepare the HCIC nanofiber membrane adsorber (HCIC‐g‐MBI). Successful preparation of the HCIC membrane adsorber was confirmed by SEM, FTIR, and XPS analyses. The HCIC membrane adsorber had a static adsorption capacity of 252 mg/g for human immunoglobulin G (IgG) under pH 7 and 0.8 mol/L Na 2 SO 4 conditions in PBS buffer. At pH 3, the recovery of IgG reached 91%, which showed a high recovery efficiency. These results indicated that the HCIC nanofiber membrane adsorber could be used in antibody purification.