Studies Of Serum Albumin Adsorption On Cibacron Blue F3GA Functional Microspheres

Poly(vinyl acetate) macromonomer with a styryl end group was synthesized by chain transfer radical polymerization in the presence of 2-mercaptethanol as chain transfer agent and end replacement reaction with p-chloromethyl styrene. The properties of macromonomer, such as molecular weight, molecular weight distribution, structure were characterized by using gel permeation chromatography (GPC), Fourier transform infrared (FTIR). It was found that molecular weight of PVAc macromonomer was 104 and the structure was clear. Poly(vinyl acetate) grafted polystyrene (PVAc-g-PSt) microspheres were obtained by dispersion copolymerization. In the case, PVAc macromonomer played an important role not only as comonomer but also as reactive stabilizer in the polymerization system. The PVAc-g-PSt microsphere has a core-shell structure with PSt as core and PVAc as shell. The morphology, structure and diameter of the microspheres were studied by using scanning electron microscopy (SEM),1H-NMR and FTIR. It was found that PVAc-g-PSt microsphere remained regular sphere configuration and the diameter kept uniform size distribution.Poly(vinyl alcohol) grafted polystyrene (PVA-g-PSt) composite microspheres were derived from alkaline hydrolysis from PVAc-g-PSt core-shell microspheres. The functional microspheres were prepared via the nucleophilic action between PVA-g-PSt microspheres and Cibacron Blue F3GA (CB). The success of the nucleophilic reaction was proved by FTIR and elemental analysis instrument, and no significant changes of size and shape were observed between PVA-g-PSt and CB functional microspheres in images of scanning electron microscopy (SEM). The amount of CB on surface of the functional microspheres was obtained by using an elemental analysis instrument. The effects of origination concentration of human serum albumin (HSA), adsorption time, pH and temperature on adsorption amount of the CB functional microspheres were studied. When the HSA concentration is 1.0 mg/mL, and pH is 5.14, the largest capacity of CB functional microspheres on HSA adsorption was 40.9 mg/g at room temperature. The interaction was further discussed by characterization of the zeta potential. The highest desorption ratio (92.11%) was achieved by using an eluent of 0.5 mol/L NaSCN (pH 8.0). The functional PVA-g-PSt microspheres could be reused without significant decreases in the adsorption capacities.