Recovery of serum proteins using cellulosic affinity membrane modified by immobilization of Cu2+ ion

Abstract

An affinity membrane was prepared from a porous cellulose membrane, and adsorption and recovery of serum proteins were investigated from the viewpoint that affinity membranes are efficacious against separation and purification of biomaterials. Into the cellulose membrane, iminodiacetate (IDA) group that acts as a ligand to metal ions was introduced (Cell–IDA membrane), and then Cu2+ ion was immobilized (Cell–IDA–Cu membrane). Bovine serum albumin (BSA) and γ-globulin (BγG), which are the major proteins in blood, were adopted as model proteins to be separated. The Cell–IDA–Cu membrane had large adsorption capacity for these proteins despite the low degree of modification. The amounts of proteins adsorbed on the Cell–IDA–Cu membrane increased with increasing pH, and BγG was adsorbed more than BSA. High protein recoveries from the Cell–IDA–Cu membrane were obtained. The separation of these proteins was also conducted under the optimum conditions of adsorption and recovery, and BγG was concentrated more than BSA although the initial concentration of BγG was lower than that of BSA. © 1996 John Wiley & Sons, Inc.