Abstract：
In this work, we investigate the nanoparticle-cell wall interaction by NiO and mixed metal oxide CuO-NiO nanoparticles. We have synthesized and characterized the nanoparticles using XRD, FESEM, EDS, UV vis. spectroscopy, FTIR, Zeta, and TEM analysis in our previous work. Furthermore, a preliminary antibacterial study showed that both the nanoparticles performed very well as antibacterial agents. In this extended work, we investigate the mechanism of interaction of NiO and CuO-NiO nanoparticles with S. aureus and E. coli cells as there are number of studies for antibacterial mechanism of CuO nanoparticles. The uptake of crystal violet dye in the outer bacterial membrane, the release of ß-galactosidase enzyme, and relative electric conductivity assay were used to investigate changes in the permeability and integrity of the cell membrane. Superoxide ions, which are produced intracellularly as ROS by nanoparticles, severely damage bacterial membranes. Zeta potential measurement, which resulted in surface charge neutralization, proved membrane instability. FTIR analysis was used to identify changes in the proteins, carbohydrates, and fatty acids that make up the chemical composition of cell surfaces. AFM imaging demonstrated extensive alteration of the nanomechanical and surface characteristics. Confocal microscopy examination supported the DNA fragmentation and nanoparticle-cell adhesion. Due to their enhanced antibacterial activity when compared to monometallic oxide nanoparticles, this study demonstrated that mixed metal oxides can be employed in the health and biomedical sectors.
摘要：
在这项工作中,我们研究了NiO和混合金属氧化物CuO-NiO纳米粒子的纳米粒子-细胞壁相互作用。我们使用XRD合成并表征了纳米颗粒，FESEM，EDS,UVvis.光谱学,FTIR,泽塔,和TEM分析在我们以前的工作。此外，一项初步的抗菌研究表明，两种纳米粒子作为抗菌剂的性能非常好。在这项扩展的工作中，我们研究了NiO和CuO-NiO纳米颗粒与金黄色葡萄球菌和大肠杆菌细胞相互作用的机制，因为有许多关于CuO纳米颗粒抗菌机制的研究。细菌外膜对结晶紫染料的吸收，β-半乳糖苷酶的释放，和相对电导率测定用于研究细胞膜通透性和完整性的变化。超氧化物离子,由纳米粒子在细胞内产生ROS，严重损害细菌膜。Zeta电位测量,导致表面电荷中和，证明了膜的不稳定性。FTIR分析用于鉴定蛋白质的变化，碳水化合物,和构成细胞表面化学成分的脂肪酸。AFM成像显示了纳米力学和表面特征的广泛改变。共聚焦显微镜检查支持DNA片段化和纳米颗粒-细胞粘附。由于它们与单金属氧化物纳米颗粒相比具有增强的抗菌活性，这项研究表明，混合金属氧化物可用于卫生和生物医学领域。
