Eco-Friendly Zinc Oxide Nanoparticles from Peppermint: Synthesis, Characterization, and Antimicrobial Evaluation

This research presents an eco-friendly technique for synthesizing zinc oxide nanoparticles (ZnONPs) using peppermint (Mentha Piperita) extract as both a reducing and stabilizing agent. The synthesis involved a controlled reaction between zinc nitrate hexahydrate [Zn(NO ₃ ) ₂ .6H ₂ O] and the Peppermint extract. The resulting ZnONPs were characterized using SEM, EDXS, TEM, XRD, FTIR, and UV-Vis spectroscopy. SEM revealed well-defined triangular crystals, while TEM showed spherical nanoparticles sized 20–50 nm. EDXS confirmed the elemental composition as Zn = 80.4% and O = 19.6%. XRD analysis validated the crystalline structure, and FTIR identified biomolecules involved in the synthesis. UV-Vis spectra displayed an absorption peak at 220 nm. Antimicrobial testing using the well diffusion method showed inhibitory zones of 0.2, 0.1, and 0.05 mm at zinc nanoparticle (ZnONPs) concentrations of 35, 25, and 15 mg/ml, respectively. The results demonstrate effective bacterial inhibition, with the highest concentration (35 mg/ml) producing the largest zone of inhibition. This eco-friendly synthesis method for ZnONPs is sustainable and holds promise for applications in antibacterial technologies and various other industries. The ZnONPs demonstrated significant antibacterial properties, suggesting their potential for further research in biological and materials science.