聚唾液酸-透明质酸接枝聚合物的合成及其在药物缓释载体中的应用

聚唾液酸(PSA)经环氧氯丙烷活化后，与透明质酸(HA)在碱性条件下反应合成了系列PSA-HA接枝聚合物(P¹~P⁵, PSA与HA质量比分别为1：1~5 ：1)，合成率40%~89%，其结构经FT-IR，元素分析和SEM表征。以胰岛素为模型药物，将P²与胰岛素按2 ：1(m/m)混合时，包封率和载药率分别为85%和38%，平均粒径为3.2 μm。体外释药试验结果表明: P²对胰岛素有一定的体外缓释能力，在6 h内释药89%；在pH 1.2条件下的释药速度大于pH 7.4条件下的释药速度。

Preparation and Application of Polysialic Acid-Hyaluronan Grafted Polymer as Drug Delivery Carrier

The grafted polymers ( P1 ~P5 ) with different mass ratio ( 1 ∶1~1 ∶5 ) of hyaluronic acid with polysialic acid were prepared by reaction of hyaluronic acid ( HA) with activated polysialic acid ( PSA) by epichlorohydrin under alkaline conditions .The synthetic ratio was about 40%~89%.The structures were characterized by FT-IR, elemental analysis and SEM .Taking insulin as a model drug , when the P2 and insulin were mixed by the ratio of 2∶1(m/m), the encapsulation efficiency and drug loading was 85%and 38%, respectively .The average particle size was 3.2 μm.In vitro release test showed a slow-release capability of the embedding insulin by P 2 .The drug release rate reached 89%within 6 h.The drug release rate was faster in pH 1.2 than that in pH 7.4.