Biosynthesis, Characterization and Antibacterial Activity of Iron Oxide Nano-Particles

Abstract

Post-burn infections caused by multidrug-resistant (MDR) bacteria have become a serious global health concern due to limited treatment options. To address this, researchers are turning to green synthesis of metal oxide nanoparticles—a safe, eco-friendly, cost-effective, and less toxic alternative to conventional physical and chemical methods. Nanoparticles synthesized through green routes avoid the need for extreme conditions, toxic chemicals, or external stabilizers, making them especially suitable for biomedical applications. In this study, iron oxide nanoparticles were synthesized using leaf extracts of Aloe barbadensis, Allium sativum, and Mentha longifolia, with ferric chloride (FeCl₃·6H₂O) as the precursor. Characterization techniques such as UV-visible spectroscopy, SEM, XRD, and FTIR confirmed successful nanoparticle synthesis. UV-Vis peaks (200–400 nm) indicated nanoparticle formation, XRD confirmed crystalline phases (magnetite, hematite, mag-hematite), and FTIR revealed functional groups (O–H, C=O, C≡C) involved in stabilization. SEM showed particle shapes ranging from spherical to cubic and irregular. The synthesized iron oxide nanoparticles demonstrated strong antibacterial activity against MDR gram-negative strains; Acinetobacter baumannii, Pseudomonas aeruginosa, and E. coli with significant zones of inhibition.