Biosynthesized ZnO-based bimetallic nanocomposite for anticancer, antimicrobial, and photocatalytic applications.

Industrial wastewater, particularly antibiotic-laden effluents, poses a significant environmental threat, necessitating efficient and sustainable remediation strategies. In this study, ZnO/Au nanocomposites were synthesized using Urtica dioica extract (ZnO/Au@UDE NCs), offering an eco-friendly alternative to conventional chemical methods. The NCs exhibited well-defined spherical and oval morphologies (40-50 nm), as confirmed by FTIR, TEM, and XRD analyses. Their photocatalytic efficiency in degrading penicillin G was optimized by adjusting key parameters, achieving rapid degradation within 130 min. The incorporation of gold nanoparticles significantly enhanced the electron-hole separation, thereby improving photocatalytic performance. Furthermore, ZnO/Au@UDE NCs demonstrated potent antibacterial activity against Escherichia coli and Pseudomonas aeruginosa (MIC: 125 µg/ml) and exhibited strong antioxidant and anticancer properties, with IC50 values of 72.49 µg/ml for MCF-7 and 23.63 µg/ml for AGS cancer cells. The combined photocatalytic and biological functionalities highlight the potential of these NCs for environmental remediation and biomedical applications, demonstrating a sustainable and multifunctional approach to nanomaterial development.