Figure 2: The effect of pH on the zeta potential of BSA immobilized anionic PP. BSA was immobilized with 37.5 mg of by anionic PP at pH 3.8 under various BSA concentrations. Anionic PP was washed with Mili-Q water the centrifuge. Wash was repeated 3 times and the anionic PP was suspended in 10 ml of Mili-Q water. pH was adjusted at 3.0 using 0.1 M of HCl aqueous solution.