Preparation and Characterization of Fe<sub>2</sub>O<sub>3</sub> and Fe<sub>2</sub>O<sub>3</sub>@Ag/AgCl Core-Shell NPs Using Mint Leaf Extract, and Study of Their Cytotoxicity and Inhibition of Breast C

Iron oxide nanoparticles (Fe2O3) and iron oxide core–silver/silver chloride shell nanoparticles (Fe2O3@Ag/AgCl) were green-synthesized using mint leaf extract .X-ray diffraction (XRD) results showed that Fe2O3 formed in two phases, γ -Fe2O3 and α -Fe2O3, while Fe2O3@Ag/AgCl formed in one phase, α -Fe2O3, with crystallite sizes increasing from 1.89 nm for Fe2O3 to 22.42 nm for Fe2O3@Ag/AgCl. Transmission electron microscopy (TEM) revealed that Fe2O3 had a heterogeneous structure with nanoclusters, while Fe2O3@Ag/AgCl exhibited a uniform Ag/AgCl coating around the iron oxide core, indicating successful coating. FTIR analysis identified peaks corresponding to Fe–O bonds at 559.56 cm–1 and 472.05 cm–1 with the presence of functional groups due to the components of the plant extract. Atomic force microscopy (AFM) showed that Fe2O3@Ag/AgCl had a smoother surface and larger crystal size (58 nm) compared to Fe2O3 (39 nm), with lower surface roughness of 3 nm compared to 12 nm for Fe2O3. UV–Vis analysis showed absorption in UV region with a plasmonic peak in the visible range, with Eg were 3.57 eV and 3.41 eV for Fe2O3 and Fe2O3@Ag/AgCl, respectively. Cytotoxicity test was performed on normal rat embryo fibroblast (REF) cells and growth inhibition test of MDA breast cancer cells using a concentration (50 μg / ml) with a series of dilutions)100%, 50%, and 25(% for two periods)24 and 48 (hours, Fe2O3@Ag/AgCl showed greater toxicity to (REF) cells, but within the permissible limits and more effective growth inhibition of breast cancer (MDA) cells compared to Fe2O3, especially after 48 hours.