介孔SiO2/PPy复合微球对布洛芬的负载与释放研究

Mesoporous SiO_2/PPy Composite Microspheres for the Loading and Release of Ibuprofen

采用胶束聚集模板法以正硅酸乙酯为硅源,溴化(-)-N-十二基-N-甲基麻碱为软模板,羧基乙基硅烷三醇钠盐为助结构导向剂,合成尺寸为120±30nm的介孔二氧化硅(mSiO_2)粒子,再以过硫酸铵为氧化剂,使用水热法包覆聚吡咯(PPy)制备出粒径为150~250 nm的介孔二氧化硅/聚吡咯复合微球(mSiO_2/PPy).通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)和红外光谱(FT-IR)对所得产物的物相、形貌和化学成分进行了表征.研究了其对布洛芬(IBU)的负载与释放行为,载药率为53.35%,包封率为21.34%.在pH=7.4的缓冲溶液中,72h内IBU释放量为68%,实现了药物缓释.因此,制备的mSiO_2/PPy复合微球为控释给药体系提供了优异的药物载体.

The mesoporous SiO2 particles with the size of 120±30 nm were synthesized by micellar ag- gregate templating method using tetraethyl orthosilicate as silicon source, （-）-N-dodecyl-N-methyl- ephedrinium bromide as a soft template and carboxy-ethylsilanetriol sodium salt as a co-structure direc- ting agent. Then with ammonium persulfate as an oxidant, the polypyrrole （PPy） were modified on the surface of mesoporous SlOe particles to obtain mSiO2/PPy composite microspheres with diameter of 150 -250 nm via hydrothermal route. The morphology, phase and chemical composition were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and Fourier transform infrared （FT- IR）. The loading and release assay of mSiO2/PPy composite microspheres to ibuprofen （IBU） were in- vestigated. It is found that the loading capacity can up to 53.35 % and the encapsulation efficiency is 21. 34%. The 68% of IBU can release within 72 h at pH 7.4, the drug sustained release is realized. Hence, the mSiO2/PPy composite microspheres provide an excellent drug carrier for controlled release system.