Enhanced Antibacterial Activity of Silver Doped Titanium Dioxide-Chitosan Composites under Visible Light

Materials

Kai Xia¹  Yingchun Li¹  Jie Li¹  Chunmao Zhao¹  Bing Xie¹  Jing Han² 

[1] School of Materials Science and Engineering, North University of China, Taiyuan 030051, China;School of Mechatronic Engineering, North University of China, Taiyuan 030051, China;

关键词: cross-linked chitosan;    silver;    titanium dioxide;    photocatalytic antibacterial;   

DOI  :  10.3390/ma11081403

来源: DOAJ

【 摘 要 】

Nano titanium dioxide (TiO2) with photocatalytic activity was firstly modified by diethanolamine, and it was then doped with broad spectrum antibacterial silver (Ag) by in situ method. Further, both Ag doped TiO2-chitosan (STC) and TiO2-chitosan (TC) composites were prepared by the inverse emulsion cross-linking reaction. The antibacterial activities of STC composites were studied and their antibacterial mechanisms under visible light were investigated. The results show that in situ doping and inverse emulsion method led to good dispersion of Ag and TiO2 nanoparticles on the cross-linked chitosan microsphere. The STC with regular particle size of 1–10 μm exhibited excellent antibacterial activity against E. coli, P. aeruginosa and S. aureus under visible light. It is believed that STC with particle size of 1–10 μm has large specific surface area to contact with bacterial cell wall. The increased antibacterial activity was attributed to the enhancement of both electron-hole separations at the surface of nano-TiO2 by the silver ions under the visible light, and the synergetic and sustained release of strong oxidizing hydroxyl radicals of nano-TiO2, together with silver ions against bacteria. Thus, STC composites have great potential applications as antibacterial agents in the water treatment field.

【 授权许可】

Unknown