Guo Lingqiao, Shan Chao, Liang Jialiang, Ni Jinren, Tong Meiping
Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Shenzhen Graduate School of Peking University, Shenzhen 518055, PR China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
Colloids Surf B Biointerfaces. 2015 Apr 1;128:211-218. doi: 10.1016/j.colsurfb.2015.01.013. Epub 2015 Jan 16.
Au@TNBs nanocomposites were synthesized by depositing Au nanoparticles onto the surfaces of TiO2 nanobelts (TNBs). The disinfection activities of Au@TNBs on model cell type, Gram-negative Escherichia coli (E. coli), were examined under visible light irradiation conditions. Au@TNBs exhibited stronger bactericidal properties toward E. coli than those of TNBs and Au NPs under visible light irradiation. The bactericidal mechanisms of Au@TNBs under light conditions were explored, specifically, the specific active species controlling the inactivation of bacteria were determined. Active species (H2O2, diffusing ∙OH, ∙O2-, 1O2, and e-) generated by Au@TNBs were found to play important roles on the inactivation of bacteria. Moreover, the concentrations of H2O2, ·OH, ·O2-, and 1O2 generated in the antimicrobial system were estimated. Without the presence of active species, the direct contact of Au@TNBs with bacterial cells was found to have no bactericidal effect. The reusability of Au@TNBs were also determined. Au@TNBs exhibited strong antibacterial activity toward E. coli even in five consecutively reused cycles. This study indicated that the fabricated Au@TNBs could be potentially utilized to inactivate bacteria in water.
通过将金纳米颗粒沉积到二氧化钛纳米带（TNBs）表面合成了金@TNBs纳米复合材料。在可见光照射条件下，检测了金@TNBs对模式细胞类型革兰氏阴性大肠杆菌（E. coli）的消毒活性。在可见光照射下，金@TNBs对大肠杆菌的杀菌性能比TNBs和金纳米颗粒更强。探索了光条件下金@TNBs的杀菌机制，具体而言，确定了控制细菌失活的特定活性物种。发现金@TNBs产生的活性物种（H2O2、扩散的∙OH、∙O2-、1O2和e-）在细菌失活中起重要作用。此外，还估计了抗菌系统中产生的H2O2、·OH、·O2-和1O2的浓度。在没有活性物种存在的情况下，发现金@TNBs与细菌细胞的直接接触没有杀菌作用。还测定了金@TNBs的可重复使用性。即使在连续五个循环中重复使用，金@TNBs对大肠杆菌仍表现出很强的抗菌活性。这项研究表明，制备的金@TNBs有可能用于使水中的细菌失活。
