Biogenic EA@α-Fe₂O₃ nanoparticles derived from Elytraria acaulis leaf extract: synthesis, characterization and biological evaluation

In this study, EA@α-Fe₂O₃ nanoparticles were synthesized via a green co-precipitation route using Elytraria acaulis (L.f.) Lindau leaf extract as a biological stabilizing medium. Ferric nitrate and sodium hydroxide were reacted under microwave irradiation during nanoparticle synthesis. The synthesized nanoparticles were characterized using UV–Vis, FTIR, SEM, TEM, EDX and PXRD. A distinct optical absorption band at 305 nm was observed, while PXRD analysis confirmed the formation of crystalline α-Fe₂O₃. FTIR analysis indicated Fe–O vibrations along with surface-associated organic functionalities. SEM and TEM revealed the morphological features and particle-size distribution, whereas Debye–Scherrer analysis of the PXRD data yielded an average crystallite size of approximately 39 nm. The nanoparticles exhibited significant antimicrobial activity against selected Gram-positive, Gram-negative and fungal strains, with an IC₅₀ value of 63.7 µg/mL in the DPPH radical-scavenging assay and an IC₅₀ value of 162.8 µg/mL for protein-denaturation inhibition. The nanoparticles also exhibited significant cytotoxic activity against A549 cells, as evidenced by a concentration-dependent reduction in cell viability, with an IC₅₀ value of 21.24 µg/mL, as determined by the MTT assay. Overall, this work highlights E. acaulis -mediated α-Fe₂O₃ nanoparticles as a multifunctional nanomaterial exhibiting antimicrobial, antioxidant, protein-denaturation inhibitory and cytotoxic activities.