Abstract:

This study demonstrated a solvothermal method of growth of three different morphologies of zinc oxide nanoparticles (ZnO NPs): i) flower-like nanorod and nanoflakes, ii) assembled hierarchical structure, and iii) nano granule. Oleic acid (C₁₈H₃₄O₂), gluconic acid (C₆H₁₂O₇) and tween 80 (C₆₄H₁₂₄O₂₆) were used as surfactant/capping/reducing agent for the formation of different morphologies of nanoparticles. The as-synthesized ZnO NPs were characterized by different physicochemical techniques such as UV-vis (UV-vis) spectroscopy, X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) analysis and dynamic light scattering (DLS) studies. Further, the antioxidant and antimicrobial activity of these nanostructures was evaluated. The antioxidant activity of these nanostructures was assessed via 2,2-diphenyl,1-1 picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and H₂O₂ free radical scavenging activity. The in vitro antimicrobial activity of the obtained nanostructures was demonstrated against both gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacterial genera. This study revealed antioxidant and antimicrobial properties of different structures of ZnO NPs suggesting their biomedical and industrial applications.

Key words: ZnO nanoparticles, Solvothermal method, Nanorods, Nanoflakes, Nano granule, Antioxidant & antimicrobial studies;