El-Shafai Nagi, El-Khouly Mohamed E, El-Kemary Maged, Ramadan Mohamed, Eldesoukey Ibrahim, Masoud Mamdouh
Department of Chemistry, Faculty of Science, Alexandria University Egypt.
Institute of Nanoscience and Nanotechnology, Kafrelsheikh University Egypt.
RSC Adv. 2019 Jan 28;9(7):3704-3714. doi: 10.1039/c8ra09788g. eCollection 2019 Jan 25.
The fabrication, characterization, and antibacterial activity of novel nanocomposites based on graphene oxide (GO) nanosheets decorated with silver, titanium dioxide nanoparticles, and zinc oxide nanoflowers were examined. The fabricated nanocomposites were characterized by various techniques including X-ray diffraction, ultraviolet-visible light absorption and fluorescence spectroscopy, Brunauer-Emmett-Teller theory analysis, Fourier transform infrared, and scanning electron microscopy. The antibacterial activity of the GO-metal oxide nanocomposites against two Gram-positive and two Gram-negative bacteria was examined by using the standard counting plate methodology. The results showed that the fabricated nanocomposites on the surface of GO could inhibit the growth of microbial adhered cells, and consequently prevent the process of biofilm formation in food packaging and medical devices. To confirm the antibacterial activity of the examined GO-nanocomposites, we examined their interactions with bovine serum albumin (BSA) and circulating tumor DNA (ctDNA) by steady-state fluorescence spectroscopy. Upon addition of different amounts of fabricated GO-nanocomposites, the fluorescence intensities of the singlet states of BSA and ctDNA were considerably quenched. The higher quenching was observed in the case of GO-Ag-TiO@ZnO nanocomposite compared with other control composites.
研究了基于用银、二氧化钛纳米颗粒和氧化锌纳米花修饰的氧化石墨烯（GO）纳米片的新型纳米复合材料的制备、表征及抗菌活性。通过包括X射线衍射、紫外-可见光吸收和荧光光谱、布鲁诺尔-埃米特-特勒理论分析、傅里叶变换红外光谱以及扫描电子显微镜在内的多种技术对制备的纳米复合材料进行了表征。采用标准计数板方法检测了GO-金属氧化物纳米复合材料对两种革兰氏阳性菌和两种革兰氏阴性菌的抗菌活性。结果表明，在GO表面制备的纳米复合材料能够抑制微生物黏附细胞的生长，从而防止食品包装和医疗器械中生物膜的形成过程。为了证实所检测的GO-纳米复合材料的抗菌活性，我们通过稳态荧光光谱研究了它们与牛血清白蛋白（BSA）和循环肿瘤DNA（ctDNA）的相互作用。加入不同量制备的GO-纳米复合材料后，BSA和ctDNA单重态的荧光强度显著猝灭。与其他对照复合材料相比，GO-Ag-TiO@ZnO纳米复合材料的猝灭程度更高。
