The current development in green synthesis of copper nanoparticles using Diospyros species: sustainable nanotechnology and biomedical applications

Abstract

Green synthesis of metal nanoparticles has emerged as a sustainable and eco-friendly alternative to conventional physicochemical methods, which often involve toxic reagents and high energy consumption. Among plant-based systems, the genus Diospyros represents a promising yet underexplored platform due to its rich phytochemical composition, including flavonoids, tannins, polyphenols, and triterpenoids, which act as natural reducing, stabilizing, and functionalizing agents. This review provides a comprehensive and mechanistic analysis of Diospyros-mediated synthesis of copper nanoparticles (CuNPs), integrating phytochemical composition with nanoparticle formation, physicochemical properties, and biological performance. A systematic literature analysis reveals that, despite the vast body of research on copper nanoparticles, relatively few studies have specifically investigated Diospyros-mediated synthesis, highlighting a significant research gap. The review critically correlates synthesis parameters (pH, temperature, precursor concentration, and extract composition) with nanoparticle characteristics such as size (10–80 nm), morphology, crystallinity, and stability. Advanced characterization techniques (UV–Vis, FTIR, XRD, SEM/TEM, XPS) are discussed to elucidate structure–property relationships and phytochemical-metal interactions. Importantly, Diospyros-derived CuNPs exhibit enhanced antimicrobial, anticancer, antioxidant, and catalytic activities due to the synergistic interplay between copper nanostructures and bioactive phytochemicals, which promotes reactive oxygen species (ROS)-mediated mechanisms, selective cytotoxicity, and improved cellular interactions. However, challenges such as poor reproducibility, lack of standardization, phytochemical variability, oxidation instability, and insufficient in vivo toxicity data limit their translational potential. Future perspectives emphasize the integration of artificial intelligence (AI) and machine learning (ML) for predictive synthesis, optimization of nanoparticle properties, and safe-by-design development. Additionally, the design of hybrid nanocomposites and systematic exploration of underutilized species such as Diospyros melanoxylon are identified as key directions. Overall, this review establishes Diospyros-mediated CuNPs as a promising platform for sustainable nanotechnology, offering a pathway toward low-toxicity, high-efficiency nanomaterials for biomedical and environmental applications.