COMPARISON OF BSA ADSORPTION AND FE SORPTION TO THE DIOL GROUP AND TANNIN IMMOBILIZED ONTO A MICROFILTRATION MEMBRANE

A diol group and tannin were immobilized on a polyethylene microfiltra tion (MF) membrane by radiation-induced grafting of glycidyl methacryl ate (GMA) and subsequent chemical modifications. A quantitative hydrol ysis of the GMA-grafted membrane with sulfuric acid provided a diol gr oup density of 7.7 mol per kg of the starting MF membrane. Coupling of the GMA-grafted membrane with tannin resulted in a 4% molar conversio n of the epoxide group. Breakthrough curves of bovine serum albumin (B SA) and ferrous ions during permeation of their solution across the mo dified membrane were compared. The breakthrough curves resulting from BSA adsorption onto the grafted polymer branches containing the diol g roup and tannin were insensitive to the residence time of the solution across the membranes, whereas the breakthrough curve of the ferrous i ons was dependent on the residence time because of their lower binding rate to the tannin immobilized on the grafted polymer branches.