应用FRAP技术评价蛋白在聚丙烯酰胺-丙烯酸凝胶中的扩散行为

药物分子从药物载体中的释放行为与载体的结构有密切关系.本实验中采用丙烯酰胺和丙烯酸等材料,运用水相沉淀的方法,制备了4种不同单体配比的聚丙烯酰胺-丙烯酸(P(Am-co-Ac))共聚物水凝胶.运用红外分析方法对P(Am-co-Ac)组成进行表征.使用荧光漂白恢复法(FRAP,fluorescence recovery after photobleaching)观察荧光素FITC标记的牛血清白蛋白(BSA)在聚丙烯酰胺-丙烯酸中的扩散行为,并以激光共聚焦显微镜进行实时成像.实验表明,FITC-BSA在不同单体配比的共聚物中的扩散系数是不同的.通过调节聚合物中单体的配比能够达到控制蛋白释放速率的作用,从而为调控蛋白和多肽类药物的缓控释放提供了可能性.

Study on the Protein Diffusion Behavior in the Poly(Acrylamide-co-Acrylic Acid) Copolymer by FRAP Technique

The drug release behavior from the carrier is bound up with the carrier′s structure.In this paper,a series of poly(acrylamide-co-acrylic acid) hydrogels with different acrylamide/acrylic acid ratios have been successfully synthesized by aqueous polymerization.These co-polymers were characterized with FTIR technique to confirm the co-polymer formation.Fluorescence recovery after photobleaching(FRAP) technique was used to investigate the diffusion behavior of fluorescein isothiocyanate labelled bovine serum albumin(FITC-BSA) in these co-polymer hydrogels,and a confocal laser scanning microscopy was applied to obtain high resolution images in real time.The results showed that the diffusion coefficient of FITC-BSA was influenced by the ratio between the acrylamide and acrylic acid in co-polymer and the co-polymer hydrogels synthesized may have potential application in controlled protein delivery system.