Zinc oxide nanoparticles (ZnO NPs) are one of the most abundant metal oxides nanoparticles. It provides excellent thermal, electrical and chemical stabilities with low biotoxicity; its photo-oxidising and photo-catalytic impact on biological and chemical species is of great importance, thereby making it a promising candidate to be used for in vitro and in vivo studies in biomedical field. Hereby, ZnO NPs were synthesized using precipitation method with zinc acetate and sodium hydroxide as starting materials. This study has characterized the synthesized ZnO NPs using different techniques such as UV-Visible spectroscopy indicating a peak at 365 nm wavelength, size of ZnO NPs was determined to be 286.7 nm by measuring hydrodynamic radii using Dynamic Light Scattering (DLS) phenomena. Further predominant charge existing at surface of the synthesised ZnO NPs was evaluated to be 31.6 mV. Anti-microbial activity of ZnO NPs was determined by Kirby-Bauer method for both Gram-positive and Gram-negative bacteria, S. aureus and E. coli, respectively. Anti-microbial activity was determined as Zone of Inhibition that measures both bactericidal and bacteriostatic activity of ZnO NPs and was found to be more potent for Gram-positive (S. aureus) bacteria and its activity increased with increasing concentration of nanoparticles. Growth kinetics was studied to determine percentage growth inhibition, for this optical density was recorded as a function of time in bacterial culture broth with and without treatment. Further DNA fragmentation assay was performed to determine genotoxicity caused by nanoparticles and its effect on genomic DNA of bacteria. Highlighting its potential role as a nano-carrier system for leading antibacterial drugs for enhanced effectiveness of the antibacterial therapies.

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氧化锌纳米颗粒的合成、表征和抗菌活性评估

氧化锌纳米粒子（ZnO NPs）是最丰富的金属氧化物纳米粒子之一。它具有优异的热稳定性、电稳定性和化学稳定性，且生物毒性低；其对生物和化学物种的光氧化和光催化作用非常重要，因此使其成为生物医学领域体外和体内研究的有希望的候选者。因此，以醋酸锌和氢氧化钠为原料，采用沉淀法合成了 ZnO NPs。本研究使用不同的技术表征了合成的 ZnO NPs，例如紫外-可见光谱，指示在 365 nm 波长处的峰值，通过使用动态光散射 (DLS) 现象测量流体动力学半径，确定 ZnO NPs 的尺寸为 286.7 nm。存在于合成的 ZnO NPs 表面的其他主要电荷被评估为 31.6 mV。ZnO NPs 的抗菌活性通过 Kirby-Bauer 法分别测定革兰氏阳性菌和革兰氏阴性菌、金黄色葡萄球菌和大肠杆菌。抗菌活性被确定为抑制区，测量 ZnO NPs 的杀菌和抑菌活性，发现对革兰氏阳性 (S. aureus) 细菌更有效，其活性随着纳米粒子浓度的增加而增加。研究生长动力学以确定生长抑制百分比，因为该光密度在经过和未经处理的细菌培养液中记录为时间的函数。进行进一步的 DNA 片段化测定以确定由纳米颗粒引起的遗传毒性及其对细菌基因组 DNA 的影响。突出其作为领先抗菌药物的纳米载体系统的潜在作用，以提高抗菌疗法的有效性。