纯硅纳米孔材料AMS-8对溶菌酶的吸附和释放**

摘要 背景：纳米介孔材料具有较高的比表面积、均一可调的孔径分布、规则的孔道结构和较强的吸附性能，是良好的酶固定化载体。目前对AMS材料的研究主要集中于合成和开发新材料方面，而对于生物分子的吸附、释放行为的研究还不多见。 目的：筛选介孔材料AMS-8吸附释放溶菌酶的最佳条件，观察不同条件对酶吸附量及释放量的影响。 方法：以阴离子表面活性剂为模板剂，3-氨丙基三甲氧基硅烷为助结构导向剂，水热法合成纯硅纳米孔材料AMS-8，结合小角度X射线粉末衍射和氮气吸附/脱附技术对合成的材料进行表征。改变酶溶液初始的浓度条件，测定吸附量的变化，在不同pH值的PBS洗脱液条件下测定释放量的变化。 结果与结论：结果显示，AMS-8具有高度有序的立方孔道径结构，比表面积达到867 m2/g，孔道直径为3.4 nm。以溶菌酶为模型分子，首先观察了AMS-8在中性(pH=7)条件下，对不同质量浓度溶菌酶的吸附行为。研究发现，当溶菌酶质量浓度为0.5 g/L时，AMS-8的最大吸附量为136 mg/g。其次，观察了溶菌酶/AMS-8体系在不同pH条件下对溶菌酶蛋白的释放行为。结果表明对于溶菌酶蛋白纳米孔材料AMS-8表现出了良好的缓释效果，其中pH值对缓释行为具有良好的调控作用。 关键词：纳米孔材料；AMS-8；溶菌酶；吸附；控制释放；纳米生物材料 doi:10.3969/j.issn.1673-8225.2010.21.015

Loading and release of lysozyme by AMS-8 mesoporous silica

Abstract BACKGROUND: Mesoporous materials have high specific surface area, uniform and controlled pore size distribution, regular pore structure and strong adsorption capacity, it is a good enzyme immobilization carrier. Current studies of AMS materials mainly focus on the synthesis and development of new materials, while few reports are abont the adsorption and release behavior of biological molecules. OBJECTIVE: To screen the best conditions for mesoporous material AMS-8 adsorbing and releasing lysozyme, and to observe the enzyme adsorption and releases in different conditions. METHODS: Mesoporous material AMS-8 was synthesized with hydrothermal method using anionic surfactant and co-structure-directing agents such as 3-aminopropyltrimethoxysilane. The materials were characterized consecutively by powder X-ray diffraction and N2 adsorption/desorption analysis. The initial concentrations of enzyme solution were changed to determine adsorption changes, the release changes were measured in PBS eluents at different pH values. RESULTS AND CONCLUSION: The calcined AMS-8 have ordered cubic cage-type mesoporous structure. The BET surface areas were 867 m2/g and the pore diameter was 3.4 nm. Lysozyme was selected as a model molecule to observe the absorption behavior of AMS-8 to lysozyme molecule under different concentrations at pH7.0. Lysozyme adsorption study suggested that the highest loading capacity was 136 mg/g at the initial concentration of 0.5 g/L. The release profile of lysozyme/AMS-8 system to lysozyme at different pH values was also investigated. The results showed that mesoporous materials AMS-8 exhibited a good sustained-release effect, and sustained manner is controlled by pH value.