Zinc oxide nanoparticles: An experimental study of synthesis, characterization and biological activity

Abstract

Zinc oxide (ZnO) nanosized structures were synthesized successfully using a benign method. The latter can be achieved by introducing sesame seed extract into the formation process of ZnO nanostructures as a reducing agent, converting zinc (Zn) ions to Zn⁰. The structural and optical properties of the prepared ZnO particles were studied using many techniques such as Ultraviolet (UV)-Vis spectrophotometry, field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). The estimated band gap energy of ZnO nanoparticles formed in the presence and absence of extract was found to be 3.94 eV and 3.88 eV, respectively, suggesting the effect of quantum confinement. The prepared particles have a flower-like shape with the appearance of small spherical particles. A Tauc plot was utilized to estimate the band gap energy of ZnO nanoparticles. The findings show that ZnO nanoparticles exhibit bactericidal properties against Staphylococcus hominins, which are Gram-positive bacteria, and also on Gram-negative bacteria such as Proteus mirabilis, E. coli, Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumonia.