Biosynthesis Of Iron Oxide Nanoparticles Using Martynia Annua Aqueous Leaf Extract, Its Antioxidant Potential And Antibacterial Ability Against Selected Wound Pathogens

Abstract

The present study demonstrates a green and eco-friendly method for the biosynthesis of iron oxide nanoparticles (Fe₂O₃ NPs) utilizing the aqueous leaf extract of Martynia annua. The reduction of FeSO₄ to iron oxide was initially indicated by a visible color change from yellow to brownish-black. UV–Vis spectroscopy confirmed the synthesis with a characteristic absorption peak at 267 nm. Functional group analysis through FTIR revealed the presence of phytochemicals such as hydroxyl groups, aldehydes, unsaturated esters, primary and aromatic amines, and alkyl halides, which likely acted as reducing and stabilizing agents. XRD analysis displayed diffraction peaks at 2θ angles of 25.68°, 13.26°, and 8.24°, confirming the crystalline nature of the nanoparticles. SEM images showed that the nanoparticles were spherical, smooth, and well-crystallized, while EDAX analysis detected strong signals for iron and trace elements like calcium, sodium, and magnesium. DLS analysis revealed an average particle size of 181.7 nm, and zeta potential studies confirmed high negative surface charge, indicating good stability and polydispersity. The synthesized iron oxide nanoparticles exhibited dose-dependent antioxidant activity and showed effective antibacterial potential against selected wound pathogens. These nanoparticles, capped with bioactive compounds from M. annua, enhance their therapeutic and biocompatible properties. The study thus highlights a simple, sustainable, and effective approach for producing iron oxide nanoparticles with promising biomedical applications.