叶酸修饰聚碳酸酯磁性载药微球的制备及其性能

Preparation and Characterization of Folate-modified Polycarbonate Magnetic Drug-loaded Microspheres

摘要:

通过十六醇（CA）引发2,2-二甲基三亚甲基环状碳酸酯（DTC）开环聚合合成了聚碳酸酯（CA-PDTC），CA-PDTC进一步与叶酸（FA）通过酯化反应合成了叶酸修饰的聚碳酸酯（CA-PDTC-FA）。采用FTIR、1HNMR和UV-vis证实了所得产物的结构。以吲哚美辛（IMC）为模型药物，Fe3O4粒子为磁源，通过乳化法制备了叶酸修饰的聚碳酸酯磁性载药微球（CA-PDTC-FA@Fe3O4）。经X射线粉末衍射仪（XRD）、热重分析仪（TG）、动态光散射仪（DLS）和振动样品磁强计（VSM）测试，分析发现：质量分数为9.5%的Fe3O4粒子被包裹在聚合物微球中，微球粒径约为320nm，有一定的超顺磁性，且对IMC的包载率为9.1%，载药微球在模拟人体环境（pH=7.4，37℃）下36 h后的累积释药量为20.0%，具有缓释效果。

Abstract:

Poly(2,2-dimethyltrimethylene carbonate)(CA-PDTC) was synthesized through ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) initiated by cetyl alcohol(CA). Folate-modified polycarbonate (CA-PDTC-FA) was synthesized via esterification reaction of CA-PDTC with folate. The structures of CA-PDTC and CA-PDTC-FA were confirmed by FTIR, 1HNMR and UV-vis. Folate-modified polycarbonate magnetic drug-loaded microspheres(CA-PDTC-FA@Fe3O4) were prepared with emulsification method, using indomethacin (IMC) as a model drug and Fe3O4 as magnetic source. X-ray powder diffraction (XRD), thermogravimetric analysis(TG), dynamic light scattering (DLS) and vibrating sample magnetometer (VSM) were used to characterize the obtained microspheres. The results showed that the mass fraction of Fe3O4 wrapped in polycarbonate microspheres was 9.5%, and that the size of microspheres was about 320 nm. Magnetic property measurement indicated that the micropheres had superparamagnetism and their saturated magnetization was 0.54emu/g. Besides, IMC with the mass percentage of 9.1% could be loaded in CA-PDTC-FA@Fe3O4 microspheres. The cumulatively released content of IMC from micropheres in PBS (pH=7.4，37℃) was 20.0% after 36 h, the result showed that the resultant microspheres had the sustained release effect for IMC.