Iron oxide nanoparticles (Fe₂O₃) stabilized with Mentha piperita obtained from Pakistan were synthesized. The study focuses on exploring the antimicrobial potential of Fe₂O₃ NPs using the agar well diffusion method. The physicochemical characteristics of the prepared Fe₂O₃ nanoparticles were studied using different techniques such as UV-Vis spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscope (SEM) analysis. The spectra obtained from FTIR, EDX, and SEM confirm the formation of Fe₂O₃. The analysis of UV-visible spectra absorption peak was found at 250 nm confirming the successful formation and stability of iron oxide nanoparticles. The NPs exhibited uniform spherical morphology with some irregular shapes and contained Fe, O, Ca, Si, Na, Mg, and Cl indicating the synthesis of Fe₂O₃ NPs. Additionally, the Fe₂O₃ NPs formed through biosynthesis demonstrated antimicrobial activities against E.coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Stable Fe₂O₃ NPs were synthesized using Mentha piperita aqueous leaf extract and revealed antimicrobial activity on E.coli, S. aureus, and P. aeruginosa.

Keywords: Mentha piperita, Fe₂O₃ NPs, P. aeruginosa, UV-visible spectroscopy.