一种pH响应型Y形两亲聚合物的合成表征及药物释放性能

Synthesis,Characterization and Drug Release Behavior of pH Sensitive Y-Shaped Amphiphilic Polymer

乙氧基乙基缩水甘油醚作为聚合单体,采用阴离子活性聚合(AROP)的方法合成了一种Y形两亲性聚合物聚乙二醇-聚乙氧基乙基缩水甘油醚(PEG-b-PEEGE),并在支点位置引入对弱酸敏感的缩酮结构。采用核磁共振和凝胶渗透色谱对其结构和相对分子质量进行表征。通过旋蒸法制备聚合物胶束,采用透射电镜和动态光散射对胶束的形貌及尺寸进行表征,结果显示聚合物胶束呈球形,平均粒径为88.36 nm。以阿霉素为模型药物考察聚合物的载药及在不同pH环境下的释放行为,结果表明这种缩酮结构的两亲性聚合物具有良好的pH响应性释放能力,即在酸性条件下(pH 4.0)的释放速率比生理pH环境下明显加快。

A Y-shaped amphiphilic polymerpoly（ethylene glycol）-b-poly（ethoxy ethyl glycidyl ether）（PEG-b-PEEGE） was prepared by living anionic ring opening polymerization（AROP）.At the branching point,a ketal group was introduced,which was degradable under acidic conditions. The chemical structure and molecular weight were characterized by1 H-NMR and GPC. Polymeric micelles were prepared through rotation-evaporation method and the morphology and size of micelles were characterized by transmission electron microscopy（TEM） and dynamic light scattering（DLS）.The results show that polymeric micelles are spherical and the average size is 88.36 nm.The encapsulation and release behavior of doxorubicin（DOX） in different pH environment were investigated. The results show that the amphiphilic polymers with ketal group possess good pH responsiveness,that is,the release rate under acidic conditions（pH 4.0） is significantly faster than that in the physiological pH environment.