Green synthesis of magnesium oxide nanoparticles using Solanum nigrum L. Leaf extract: a multifaceted approach for sustainable biomedical and photoprotective applications

This study outlines the eco-friendly synthesis of magnesium oxide nanoparticles (MgO NPs) using Solanum nigrum L. leaf extract as a reducing agent. Characterized by UV-Vis spectroscopy (λmax at 293 nm, direct/indirect bandgaps of 2.5 and 2.79 eV), XRD (confirming face-centered cubic structure, crystallite size 25.97 ± 1.55 nm), and SEM (showing uniform cubic morphology, average size 38.39 nm), the NPs displayed significant biological activities. They exhibited potent antioxidant effects (DPPH IC50 0.46 ± 0.05 mg/mL; ABTS IC50 0.42 ± 0.07 mg/mL; FRAP 294.16 ± 7.38 mM Fe2+/g; total antioxidant 212.96 ± 2.73 mg AAE/g), strong anti-inflammatory properties (egg albumin IC50 0.374 ± 0.02 mg/mL; HSA IC50 0.682 mg/mL), notable antidiabetic potential (α-amylase IC50 29.03 ± 2.43 mg/mL; α-glucosidase IC50 48.28 ± 2.06 mg/mL), and promising anti-Alzheimer activity (AChE inhibition IC50 64 ± 1.33 mg/mL). The NPs also showed excellent photoprotective properties (SPF 42 ± 1.5). These results underscore the multifunctional biomedical applications of green-synthesized MgO NPs, merging sustainability with therapeutic potential for pharmaceutical and cosmetic uses.