Department of Petrochemical Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, 31900 Kampar, Perak, Malaysia.
Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, 31900 Kampar, Perak, Malaysia.
J Photochem Photobiol B. 2018 Oct;187:66-75. doi: 10.1016/j.jphotobiol.2018.07.030. Epub 2018 Aug 3.
Flower-like ZnO micro/nanostructures were successfully fabricated via a surfactant-free co-precipitation method. The as-synthesized product was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence (PL) analyses. In the presence of visible light irradiation, the as-synthesized flower-like ZnO showed higher antibacterial activities against Enterococcus faecalis (E. faecalis) and Micrococcus luteus (M. luteus) than that of commercial ZnO. The excellent antibacterial performance of synthesized flower-like ZnO was also observed via the bacterial morphological change, K ions leakage and protein leakage in extracellular suspension. In addition, the FTIR investigation on both treated bacteria further confirmed the bacterial membrane damage via cellular substance alteration. The enhancement of the antibacterial activity of synthesized ZnO can be attributed to the unique flower-like morphology which can increase the surface OH groups and the quantity of photogenerated electron-hole pair available to participate in the photocatalytic reaction. The reactive oxidizing species (ROS) scavengers experiments showed that HO played a main role in the photocatalytic antibacterial process. Our study showed that the synthesized flower-like ZnO micro/nanostructures can act as efficient antibacterial agents in the photocatalytic antibacterial process under visible light irradiation.
通过无表面活性剂共沉淀法成功制备了具有花状形貌的 ZnO 微/纳米结构。采用 X 射线衍射（XRD）、场发射扫描电子显微镜（FESEM）、能谱（EDX）、透射电子显微镜（TEM）、傅里叶变换红外光谱（FTIR）、紫外-可见漫反射光谱（UV-vis DRS）和光致发光（PL）分析对合成产物进行了表征。在可见光照射下，所合成的花状 ZnO 对粪肠球菌（E. faecalis）和藤黄微球菌（M. luteus）的抗菌活性明显高于商用 ZnO。通过细菌形态变化、胞外悬浮液中 K+离子泄漏和蛋白质泄漏观察到合成花状 ZnO 的优异抗菌性能。此外，对处理过的细菌进行的 FTIR 研究进一步证实了通过改变细胞物质导致的细胞膜损伤。合成 ZnO 抗菌活性的增强可归因于独特的花状形貌，这可以增加表面 OH 基团的数量和可参与光催化反应的光生电子-空穴对的数量。活性氧（ROS）清除剂实验表明，HO 在光催化抗菌过程中起主要作用。我们的研究表明，所合成的花状 ZnO 微/纳米结构在可见光照射下的光催化抗菌过程中可以作为有效的抗菌剂。
