载银纳米TiO2抗菌剂的制备及抗菌性能研究

Preparation and antibacterial activity study of Ag-embedded nano-titania material

采用四氯化钛自生晶种水解法制备了纳米TiO2，通过在水解过程中引入硝酸银制得载银纳米TiO2。对载银前后的纳米TiO2进行了XRD和TEM表征。XRD图谱表明，纳米TiO2属于锐钛矿晶型结构，水解过程中加入硝酸银得到纳米TiO2与氯化银的复合体（AgCl／TiO2）。TEM照片显示，纳米TiO2样品为分散较好的20-30nm之间的粒子，而载银后的复合物粒子明显增大，有轻度的团聚发生。采用抑菌环、悬浮液浊度法测定了载银前后纳米TiO2的抗菌性能，结果表明，AgCl／TiO2抗菌材料对金黄色葡萄球菌有明显的抑菌效果，其最小抑菌浓度为750mg／L。达到日本制定的“银等无机抗菌剂自主规格及其抗菌实验法”规定的〈800mg／L指标。

Nano-titania was prepared by spontaneous seed crystal thermo-hydrolysis of industrial aqueous TiCl4 solution, and Ag-embedded nano-titania was synthesized through adding AgNO3 during the process of thermo-hydrolysis of TiCl4. XRD and TEM characterization of these two samples were performed. The XRD results suggest that nano-titania prepared belongs to anatase structure, and the Ag-embedded nano-titania belongs to the complex of nano-titania and AgCl. The TEM pictures illuminates that the particles of titania is about 20-30nm and well dispersed. However, the particles of Ag-embedded nano-titania are obviously bigger than those of pure titania. The antibacterial activity of Ag-embedded nano-titania was studied, and the results suggest that it possess distinct antibacterial ability to staphylococcus aureus with the value of minimal inhibitory concentration （MIC） as 750mg/L, which is smaller than the standard value （800g/L） of inorganic antibacterial in Japan.