Green synthesis of AgCu2O nanocomposites via Melastoma saigonense extract: Physicochemical characterization and multifunctional bioenvironmental applications

Abstract

The present research emphasizes production of eco-friendly AgCu₂O nanocomposites from a medicinal plant extract derived from Melastoma saigonense (Kuntze) Merr. seeds. AgCu₂O samples at varying Ag concentrations (1, 3, and 5 mol%) were produced and then characterized using thermogravimetric analysis (TGA), X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance (UV–Vis DRS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectrometry (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), a vibrating-sample magnetometer (VSM) and dynamic light scattering (DLS). The formation of AgCu₂O was validated by XRD, FTIR, and XPS results. A morphological investigation combined with EDS demonstrated that Ag nanoparticles appear to cover the surface of Cu₂O nanoparticles, producing AgCu₂O, whereas phytochemicals function as gel-like clusters on the surface of nanocomposites. The AgCu₂O samples were spherical, with particle sizes ranging from 3.08 to 16.47 nm. Addition of 3 mol% Ag to Cu₂O produced a 3 %AgCu₂O with smaller particle sizes (about 6.73 nm) and higher colloidal stability. In comparison to other samples with different silver loadings, 3 %AgCu₂O exhibited higher saturated magnetization (M_S) and enhanced antibacterial activity. In the assays for α-Amylase and α-Glucosidase inhibition, the IC₅₀ values of 3 %AgCu₂O were 6.19 μg/mL and 95.14 μg/mL. The cytocompatibility of the 3 %AgCu₂O was evaluated using RAW 264.7 cells, which showed no toxicity to macrophages and suppressed LPS-induced nitric oxide overproduction. Furthermore, the adsorption of methylene blue (MB) by 3 %AgCu₂O was 84.6 % under dark conditions. The resultant nanocomposite may be used for biomedical applications and environmental remediation.