College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, PR China.
Colloids Surf B Biointerfaces. 2012 Mar 1;91:162-7. doi: 10.1016/j.colsurfb.2011.10.055. Epub 2011 Nov 3.
An oil in water interface radical polymerization was used to prepare felodipine-loaded polymerized-N-maleoylchitosan (p-NMCS) and poly(lactic acid) (PLA)/p-NMCS capsules. Dynamic Light Scattering, Field Emission Scanning Electron Microscopy and Transmission Electron Microscope characterization revealed that both the p-NMCS and PLA/p-NMCS microcapsules had a ~550 nm hydrodynamic diameter, regular spherical morphology and an obvious core-shell structure. The ratio of PLA to p-NMCS in PLA/p-NMCS microcapsules was found affecting the drug loading content and entrapment efficiency. In vitro release kinetic results indicated that the p-NMCS microcapsules had a fast release rate comparing with that of the PLA/p-NMCS core-shell microcapsules, suggesting the release mechanism of the p-NMCS microcapsules was a diffusion-driven process, while the release mechanism of the PLA/p-NMCS microcapsules with high ratio of PLA to p-NMCS (not less than 1/1) was a combined diffusion and degradation-driven process.
采用油包水界面自由基聚合的方法制备了载非洛地平的聚合-N-马来酰化壳聚糖(p-NMCS)和聚乳酸(PLA)/p-NMCS 胶囊。动态光散射、场发射扫描电子显微镜和透射电子显微镜的表征结果表明，p-NMCS 和 PLA/p-NMCS 微胶囊均具有约 550nm 的水动力直径、规则的球形形态和明显的核壳结构。PLA/p-NMCS 微胶囊中 PLA 与 p-NMCS 的比例影响了载药量和包封效率。体外释放动力学结果表明，p-NMCS 微胶囊的释放速率明显快于 PLA/p-NMCS 核壳微胶囊，表明 p-NMCS 微胶囊的释放机制为扩散驱动过程，而 PLA 与 p-NMCS 比例较高的 PLA/p-NMCS 微胶囊(不低于 1/1)的释放机制为扩散和降解联合驱动过程。
