BACTERICIDAL EFFECTIVENESS OF FREEZE-CAST CERAMIC FILTERS IMPREGNATED WITH SILVER NANOPARTICLES

ABSTRACT This work aimed to produce freeze-cast pellets of porous ceramic filters of alumina and kaolinite impregnated with silver nanoparticles and to test the efficiency of bactericidal effects. Silver nanoparticles were characterized by average particle size, zeta potential and TEM. After impregnation, leached water was analyzed by graphite furnace atomic absorption spectrometry (GFAAS) that showed an efficiency of more than 99.9% in silver impregnation. From SEM/EDS, it was possible to observe that the pellets have a homogeneous distribution of silver nanoparticles. A halo of inhibition detected by the disc diffusion test shows a strong bactericidal effect of the filters.

摘要
本研究旨在制备负载银纳米颗粒的氧化铝-高岭土基多孔陶瓷过滤器冷冻铸造颗粒，并测试其杀菌效能。通过平均粒径、Zeta电位及透射电子显微镜（Transmission Electron Microscopy, TEM）对银纳米颗粒进行表征。浸渍处理完成后，采用石墨炉原子吸收光谱法（Graphite Furnace Atomic Absorption Spectrometry, GFAAS）对浸出液开展分析，结果表明银纳米颗粒浸渍效率可达99.9%以上。借助扫描电子显微镜/能量色散X射线能谱（SEM/EDS）可观察到，该颗粒表面银纳米颗粒分布均匀。通过纸片扩散法检测得到的抑菌圈证实，该过滤器具备优异的杀菌性能。