Chen Ai-Zheng, Li Yi, Chen Dong, Hu Jun-Yan
Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
J Mater Sci Mater Med. 2009 Mar;20(3):751-8. doi: 10.1007/s10856-008-3633-9. Epub 2008 Nov 6.
5-fluorouracil-SiO(2)-poly(L-lactide) (5-Fu-SiO(2)-PLLA) microcapsules were prepared in a novel process of solution-enhanced dispersion by supercritical CO(2) (SEDS). The SiO(2) nanoparticles were loaded with 5-Fu by adsorption at the first place, then the 5-Fu-SiO(2) nanoparticles were coated with PLLA by a modified SEDS process. The resulted microcapsules were characterized by scanning electron microscope (SEM), laser diffraction particle size analyzer, Fourier transform infrared spectrometer (FTIR) and thermogravimeter-differential scanning calorimeter (TG-DSC). The drug load, encapsulation efficiency and drug release profiles were also determined. The resulted microcapsules exhibited a rather spherical shape, smooth surface, and a narrow particle size distribution with a mean particle size of 536 nm. The drug load and encapsulation efficiency of the samples were 0.18% and 80.53%, respectively, 25.05% of 5-Fu was released in the first half hour, then drug released in a sustained process, which was much slower than that of without coated by PLLA. The results indicated that the modified SEDS process could be used to produce drug-polymer microcapsules with a core-shell structure, high encapsulation efficiency and sustained drug release effect.
采用超临界CO₂溶液增强分散法（SEDS）这一新型工艺制备了5-氟尿嘧啶-二氧化硅-聚（L-丙交酯）（5-Fu-SiO₂-PLLA）微胶囊。首先通过吸附作用将5-Fu负载于SiO₂纳米颗粒上，然后采用改进的SEDS工艺用PLLA包覆5-Fu-SiO₂纳米颗粒。通过扫描电子显微镜（SEM）、激光衍射粒度分析仪、傅里叶变换红外光谱仪（FTIR）和热重-差示扫描量热仪（TG-DSC）对所得微胶囊进行了表征。还测定了载药量、包封率和药物释放曲线。所得微胶囊呈现出相当规则的球形，表面光滑，粒径分布狭窄，平均粒径为536 nm。样品的载药量和包封率分别为0.18%和80.53%，5-Fu在前半小时释放了25.05%，随后药物持续释放，其释放速度比未用PLLA包覆的情况慢得多。结果表明，改进的SEDS工艺可用于制备具有核壳结构、高包封率和药物缓释效果的药物-聚合物微胶囊。
