Biosynthesis of iron oxide nanoparticles and their antimicrobial and biocompatibility studies: a sustainable approach

In the present study, magnetic iron oxide nanoparticles (IONPs) were successfully synthesized using Acacia concinna pod extract as a natural bio-reducer and stabilizing agent. Field Emission Scanning Electron Microscopy revealed a heterogeneous morphology comprising both spherical and rod-shaped nanoparticles. The spherical particles exhibited an average diameter of 100-200 nm, while the rod-shaped particles demonstrated an aspect ratio of 2.49. Vibrating Sample Magnetometry analysis indicated a saturation magnetization of 54.284 emu/g, and Brunauer-Emmett-Teller analysis determined a specific surface area of 59.851 m²/g. The presence of diverse biomolecules in the A. concinna extract was confirmed using various analytical techniques. Among them, pentadecanoic acid was found to play a crucial role in the synthesis mechanism of IONPs. Furthermore, X-ray Photoelectron Spectroscopy analysis showed Fe 2p₃/₂ and Fe 2p₁/₂ binding energies at 708.2 eV and 721.85 eV, respectively, validating the formation of Fe₂O₃. The synthesized IONPs exhibited no antimicrobial activity against several tested bacteria, including Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, as well as fungi, such as Penicillium spp., Aspergillus flavus, Fusarium oxysporum, and Rhizoctonia solani. Biocompatibility studies on the L929 normal fibroblast cell line revealed that the synthesized IONPs did not exhibit cytotoxicity, further supporting their potential as a biocompatible material. This makes them potential candidate for use in drug delivery systems as well as in various therapeutic and diagnostic applications.

The online version contains supplementary material available at 10.1007/s13205-025-04571-4.