Biosynthesis of Zinc Oxide Nanoparticles and Their Cytotoxicity Study on Fibroblast Cell Line Using MTT Assay

This study explores the green synthesis, characterization, and cytotoxicity of zinc oxide nanoparticles (ZnO NPs) derived from Cassia fistula leaves extract. The biosynthesized ZnO NPs were characterized using UV-Vis spectroscopy, FTIR, PXRD, FESEM, HRTEM, and EDAX analysis. UV-Vis and FTIR confirmed the formation of ZnO NPs and the presence of functional groups involved in the synthesis. PXRD analysis determined the average crystalline size to be 14.91 nm, while FESEM and HRTEM revealed a hexagonal wurtzite structure with irregular morphology. EDAX confirmed a zinc content of 70.5%. The cytotoxicity of ZnO NPs was evaluated on a non-cancerous fibroblast cell line (NIH-3T3) using the MTT assay, demonstrating an IC50 value of 38.56 µg/mL. ZnO NPs has higher cytotoxicity and lower cell viability than commercial ZnO sample, even at low concentrations. Thus, this study highlights ZnO NPs to be sustainable and cost-effective biomedical alternative, warranting additional research into their anticancer and antibacterial properties.