功能化PVA-g-PSt微球对牛血清蛋白的吸附研究

由大分子单体法制得了聚醋酸乙烯酯接枝聚苯乙烯(PVAc-g-PSt)微球,使该微球在碱性条件下醇解形成了聚乙烯醇接枝聚苯乙烯(PVA-g-PSt)微球.经X射线光电子能谱对PVA-g-PSt微球表层组成的表征,发现微球具有以PVA为壳、PSt为核的核壳结构.进而利用汽巴蓝F3GA(CB)与PVA-g-PSt微球进行亲核反应,制得了CB功能化的PVA-g-PSt微球,由元素分析定量出了固定在微球表面的CB含量.用透射电子显微镜对微球的粒径与形态进行了表征,发现微球表面在CB功能化后变得相对粗糙,粒径大小基本保持不变,但形态更加规整.比较了3种不同微球对蛋白质的吸附,考察了吸附动力学和影响吸附的因素,发现起始牛血清蛋白(BSA)浓度、pH值、离子强度对微球吸附BSA有明显的影响,并利用Zeta电位探讨了微球与蛋白质间的相互作用机理.最后用硫氰酸钠(NaSCN)进行解吸,计算解吸率最高可达到95.7%,该CB功能化微球可以重复利用,吸附率仅减少5.3%.

STUDIES OF PROTEIN ADSORPTION ON CIBACRON BLUE F3GA FUNCTIONAL PVA-g-PSt MICROSPHERES

Poly(vinyl acetate) grafted polystyrene(PVAc-g-PSt) microspheres with PVAc chains on their surfaces were prepared by macromonomer method.Then,poly(vinyl alcohol) grafted polystyrene(PVA-g-PSt) microspheres was derived from alkaline hydrolysis ofPVAc-g-PSt in the presence of NaOH.X-ray photoelectron spectroscopy analysis(XPS) of the microsphere surfaces indicated that PVA chains were favorably located on their surfaces of the PVA-g-PSt microspheres.The functional microspheres were prepared via the nucleophilic action between PVA-g-PSt microspheres and Cibacron Blue F3GA(CB).CB amount on surfaces of the functional microspheres were obtained by using an elemental analysis instrument.The adsorption mechanism,adsorption kinetic equation,ion strength and pH influence of three typical functional polymeric microspheres for BSA were studied.The interaction was further discussed by characterization of the zeta potential.The highest desorption ratio(95.7%) was achieved by using an eluent of 0.5mol/L NaSCN(pH 8.0).The functional PVA-g-PSt microspheres could be reused without significant decreases in the adsorption capacities.