摘要
目的:观察聚乙烯醇在聚苯乙烯微球表面对非特异性蛋白吸附的阻抗效果,考察聚乙烯醇水解度的影响,并与聚氧化乙烯-聚氧化丙烯-聚氧化乙烯三嵌段共聚物比较。方法:①用无皂乳液聚合法制备单分散聚苯乙烯微球:平均粒径416nm,电泳迁移率-2.69[10-8m2/(V·s)]。②微球凝并状况测定:在聚苯乙烯微球悬浮液中加入聚合物水溶液,使微球在室温预吸附聚合物2h,然后与溶菌酶溶液混合,于25℃恒温2h后取样测定表观粒径,由表观粒径的变化评价因蛋白吸附诱发微球凝并的程度。③絮凝实验:将预吸附聚合物的聚苯乙烯微球悬浮液与溶菌酶混合,于37℃恒温24h后观察絮凝状况,进而判断预吸附聚合物对蛋白吸附的阻抗性能。④蛋白吸附的定量测定:采用高速离心/液相蛋白浓度测定法分析蛋白在聚苯乙烯微球表面吸附后,液相蛋白浓度的下降值,由此推算蛋白吸附量。结果:①未经处理的聚苯乙烯微球与溶菌酶混合后发生凝并(25℃)和絮凝(37℃),而预吸附聚合物的聚苯乙烯微球与蛋白混合后,25℃时凝并程度减轻,在高温(37℃)时预吸附了低水解度(86%)聚乙烯醇或聚氧化乙烯-聚氧化丙烯-聚氧化乙烯三嵌段共聚物的微球不发生絮凝。②预吸附了低水解度聚乙烯醇的微球,蛋白吸附量下降了79%,该聚乙烯醇的抗蛋白吸附效果优于聚氧化乙烯-聚氧化丙烯-聚氧化乙烯及水解度为99%的聚乙烯醇。结论:①通过预吸附水溶性聚合物可抑制蛋白在聚苯乙烯微球表面吸附、聚集,水解度为86%的聚乙烯醇抗蛋白吸附效果显著优于水解度为99%的聚乙烯醇,也优于聚氧化乙烯-聚氧化丙烯-聚氧化乙烯三嵌段共聚物。②微球的絮凝测试提供了一种快速评价预吸附聚合物抗蛋白吸附性能的方法,所获得的定性评价结果与定量测试数据一致。
AIM： To study non-specific protein adsorption resistance of polyvinyl alcohol （PVA） on polystyrene （PS） microsphere surface, investigate the effect on protein inhibition by the hydrolysation （DH） degree of PVA, and compare the inhibition efficiency of PVA to that of polyethylene oxide （PEO）-polypropylene oxide （PPO）-PEO tri-block copolymer.
METHODS： ①Mono-dispersed PS microsphere was prepared by soap-free emulsion polymerization, which had an average diameter of 416 nm and electrophoretic mobility of -2.69 [10^-8 m^2/（V·s）].②Aggregation of PS suspension： PS microsphere was treated in aqueous suspension with different polymers at room temperature for 2 hours, then lysozyme was added. Apparent diameter of the particles in the suspension was measured at 25 ℃ 2 hours later. Aggregation of PS microsphere was evaluated by the apparent diameter and was correlated to protein adsorption on PS surface.③ Flocculation experiment： Aqueous suspension of PS microsphere pre-adsorbed with a polymer was mixed with lysozyme solution at 37 ℃ for 24 hours. Flocculation of the suspension was observed to judge the protein resistance of the polymers used in the pre-adsorption treatment. ④ Quantitative analysis of protein adsorption： Ultra-centrifuge and spectrophotometry were employed to figure out protein concentration in the aqueous phase of PS microsphere. The amount of protein adsorbed on PS surface was calculated based on the decreased protein concentration in the supernatant solution. RESULTS： ①In the presence of lysozyme, native PS microsphere suspension aggregated at 25 ℃ and flocculated at 37 %. Pre-adsorption of polymers on PS surface resulted in a weaker aggregation at 25 %. Upon heating at 37 ℃, no flocculation occurred when PS microsphere was pretreated by PVA with a DH degree of 86% （PVA-1） or by PEO-PPO-PEO copolymer. ②The amount of protein adsorption was decreased by 79% when the polymer for the pre-adsorpUon was PVA-1, which exhibited a better resistance to protein adsorption than the PEO-PPO-PEO and PVA with a DH degree of 99%.
CONCLUSION： ①Pre-adsorption of water-soluble polymer on PS microsphere surface can inhibit protein adhesion on the surface. PVA-1 provides much better protein resistance than PVA with a DH degree of 99%, and is even superior to the PEO-PPO-PEO copolymer. ② Good agreements between the flocculation test and quantitative measurement of protein adsorption indicate that flocculation test of PS suspension can be a simple and effective method to qualitatively evaluate the protein absorption resistance of polymers used in pre-adsorption treatment of materials surface.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2007年第31期6165-6168,共4页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
国家自然科学基金资助项目(20674003)~~
