Green synthesis, characterization, and in vitro and in vivo biological screening of iron oxide nanoparticles (Fe₃O₄) generated with hydroalcoholic extract of aerial parts of Euphorbia milii

In this work, iron oxide nanoparticles (IONPs) were synthesized using green methods. The structural morphological and optical properties of nanoparticles (NPs) were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible spectroscopy, and Fourier transform infrared spectroscopy. Based on the SEM analysis, spherical NPs with a size distribution in the range of 50-70 nm were simulated with slight variations in shapes, and the corresponding XRD was calculated. The calculated XRD patterns were then averaged. Well-defined crystalline structure of a single-phase spinel structure and a spherical shape of IONPs were observed. The in vitro and in vivo biological activities of IONPs synthesized with the hydroalcoholic extract of Euphorbia milii's aerial parts were studied. The antibacterial effects were evaluated against Staphylococcus aureus, and the enzyme inhibitory effects of the IONPs and E. milii extract on various enzymes were assessed. The IONPs demonstrated significant inhibitory activity against urease (89.09% inhibition), α-glucosidase (72.87% inhibition), carbonic anhydrase II (87.09% inhibition), and xanthine oxidase (85.09% inhibition). The E. milii extract also exhibited considerable inhibition of these enzymes. The IC₅₀ values for urease, α-glucosidase, carbonic anhydrase II, and xanthine oxidase inhibition by IONPs were 26.09, 59.09, 0.18, and 7.71 μg·mL⁻¹, respectively. The anticancer activity of the IONPs and crude extract was also evaluated. The minimum IC₅₀ values were recorded against MDR 2780AD, i.e., 0.85 (extract) and 0.54 (IONPs). Both of the tested samples were found to be significant (p < 0.001) analgesic and anti-inflammatory. In contrast, the IONPs were found sedative at all tested doses, and the extract showed a significant (p < 0.01) sedative effect at higher doses only.