Makhetha Thollwana Andretta, Ray Sekhar Chandra, Moutloali Richard Motlhaletsi
Department of Chemical Sciences, Faculty of Science, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, Johannesburg, South Africa.
DST/Mintek Nanotechnology Innovation Centre - UJ Water Research Node, Faculty of Science, University of South Africa, Private Bag X6, Florida, Science Campus, Christiaan de Wet and Pioneer Avenue, Florida Park, Johannesburg 1710, South Africa.
ACS Omega. 2020 Apr 24;5(17):9626-9640. doi: 10.1021/acsomega.9b03215. eCollection 2020 May 5.
The rational approach motivated the design of novel antimicrobial silver and silver-copper bimetallic nanoparticles contained within zeolitic imidazolate framework-8 supported on graphene oxide (GO), Ag@ZIF-8@GO, and AgCu@ZIF8@GO. In the resultant composites, ZIF-8 was able to prevent the stacking of GO sheets and also acted as a carrier for the nanoparticles within its cavities. GO, on the other hand, acted as an anchoring support enabling uniform dispersion of the nanocomposites, thus eliminating their aggregation. The morphological and physicochemical properties of the composites were determined through a variety of characterization techniques, for example, transmission electron microscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, p-X-ray diffraction (XRD), nitrogen sorption, and X-ray photoelectron spectroscopy (XPS). The energy-dispersive system and XPS supplied evidence of the presence of all expected components in the composites. The XRD provided proof of a crystalline, distorted ZIF-8 structure. Ag@ZIF8@GO and Ag-Cu@ZIF-8@GO composites were effective against both Gram-negative () and Gram-positive () bacteria as determined by the disc diffusion method. The role of silver nanoparticles (AgNPs) in the antibacterial activity of both Ag@ZIF8@GO and AgCu@ZIF8@GO was highlighted as crucial in the probable pathway in the antimicrobial activity of the composites.
这种合理的方法推动了新型抗菌银和银铜双金属纳米颗粒的设计，这些纳米颗粒包含在负载于氧化石墨烯（GO）上的沸石咪唑酯骨架-8（ZIF-8）中，即Ag@ZIF-8@GO和AgCu@ZIF8@GO。在所得的复合材料中，ZIF-8能够防止GO片层的堆叠，并且在其孔腔内充当纳米颗粒的载体。另一方面，GO充当锚固支撑，使纳米复合材料均匀分散，从而消除它们的聚集。通过多种表征技术确定了复合材料的形态和物理化学性质，例如透射电子显微镜、扫描电子显微镜、傅里叶变换红外光谱、p-X射线衍射（XRD）、氮吸附和X射线光电子能谱（XPS）。能量色散系统和XPS提供了复合材料中所有预期成分存在的证据。XRD证明了ZIF-8结构的晶体畸变。通过纸片扩散法测定，Ag@ZIF8@GO和Ag-Cu@ZIF-8@GO复合材料对革兰氏阴性菌（）和革兰氏阳性菌（）均有效。银纳米颗粒（AgNPs）在Ag@ZIF8@GO和AgCu@ZIF8@GO抗菌活性中的作用在复合材料抗菌活性的可能途径中被强调为至关重要。
