Protein Purification Using Immobilized Metal Affinity Porous Sheet

Abstract

An immobilized metal affinity porous sheet was prepared by radiation-induced graft polymerization and subsequent chemical modifications. A 2-mm thick porous sheet, made of polyethylene, with a pore size and porosity of 1.3μm and 75%, respectively, was irradiated with electron beam. An epoxy-group-containing vinyl monomer was graft-polymerized onto the irradiated porous sheet, followed by the conversion of the epoxy group into an iminodiacetate group. The resultant chelating porous sheet was cut into disks 13 mm in diameter suitable for the packing into the cylindrical cartridge. Nickel ions were immobilized before the permeation of a histidine (His) -tagged fusion protein solution through the porous sheet. Purification of His-tagged fusion green fluorescent proteins was demonstrated in a permeation mode using the nickel-ion-immobilized metal affinity porous sheet.