Centre for Surface Chemistry and Catalysis, K.U. Leuven, Kasteelpark Arenberg 23, 3001 Leuven, Belgium.
Int J Pharm. 2010 Sep 15;397(1-2):84-91. doi: 10.1016/j.ijpharm.2010.06.053. Epub 2010 Jul 7.
Amorphous microporous silica (AMS) xerogel materials were synthesized in an acid-catalyzed sol-gel process. The porosity of AMS was adapted by varying sol-gel synthesis parameters including the molar hydrolysis ratio (r-value), HCl:Si molar ratio, the type of silicon alkoxide source and the solvent. AMS particles of millimeter size were loaded with ibuprofen, by heat treatment and melt impregnation. In vitro release experiments were performed in simulated gastric and intestinal fluid. The release kinetics were critically depending on the AMS particle size distribution and the micropore diameter. The release was interpreted as configurational diffusion in the AMS micropores. The stability of unloaded and ibuprofen loaded AMS material upon storage was investigated using nitrogen physisorption, DSC analysis and in vitro release experiments. Ibuprofen loaded AMS formulations show remarkable stability, which can be attributed to the presence of ibuprofen molecules in the channels, functioning as scaffolds to support the pore structure.
无定形微孔硅 (AMS) 气凝胶材料是通过酸催化溶胶-凝胶工艺合成的。通过改变溶胶-凝胶合成参数，包括摩尔水解比 (r 值)、HCl:Si 摩尔比、硅烷醇盐源的类型和溶剂，可以调节 AMS 的孔隙率。将毫米尺寸的 AMS 颗粒用布洛芬进行热处理和熔融浸渍。在模拟胃液和肠液中进行了体外释放实验。释放动力学主要取决于 AMS 颗粒的粒度分布和微孔直径。释放被解释为在 AMS 微孔中的构象扩散。使用氮气物理吸附、DSC 分析和体外释放实验研究了未负载和负载布洛芬的 AMS 材料在储存过程中的稳定性。负载布洛芬的 AMS 制剂表现出显著的稳定性，这可归因于布洛芬分子存在于通道中，作为支撑孔结构的支架。
