ABSTRACT In this study, we carried out a simple surface modification of zinc oxide nanoparticles (ZnO NPs) using didodecyldimethylammonium bromide (DDAB) as a cationic surfactant. The crystallographic properties, optical absorption, and morphology of the ZnO NPs did not change after the surface modification. The FT-IR spectra of the surface-modified ZnO NPs (SM-ZnO) showed the characteristic peaks of DDAB, which shifted to higher frequencies with an increase in the DDAB content. The zeta potential of the SM-ZnO NPs increased with an increase in the DDAB content and reaction time. The sedimentation test results revealed that the SM-ZnO NPs exhibited better dispersion and lower aggregation than pure ZnO NPs. The SM-ZnO NPs showed high surface positive charge, thereby generating additional Zn2+ with higher surface tendency to the bacteria. The SM-ZnO NPs showed improved antibacterial activity against both Staphylococcus aureus and Escherichia coli strains as compared to the pure ZnO NPs.

中文翻译：

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提高氧化锌纳米粒子抗菌活性的简便方法

摘要 在本研究中，我们使用双十二烷基二甲基溴化铵 (DDAB) 作为阳离子表面活性剂对氧化锌纳米粒子 (ZnO NPs) 进行了简单的表面改性。ZnO NPs 的晶体学特性、光吸收和形貌在表面改性后没有改变。表面改性的 ZnO NPs (SM-ZnO) 的 FT-IR 光谱显示出 DDAB 的特征峰，随着 DDAB 含量的增加，该峰向更高的频率移动。SM-ZnO NPs 的 zeta 电位随着 DDAB 含量和反应时间的增加而增加。沉降试验结果表明，SM-ZnO NPs 比纯ZnO NPs 表现出更好的分散性和更低的聚集。SM-ZnO NPs 显示出高表面正电荷，从而产生额外的 Zn2+，对细菌具有更高的表面倾向。