Biosynthesis of Metallic Nanoparticles Using Plant Extracts: Mechanisms, Advances, and Sustainable Applications

Growing concerns over the environmental and health impacts of conventional nanoparticle synthesis have driven a shift toward green, plant-based methods. This review highlights the biosynthesis of nanoparticles using plant extracts as a sustainable, economical and non-toxic alternative. Plant-derived phytochemicals such as flavonoids, phenolics, and alkaloids serve dual roles as natural reducing and stabilizing agents, enabling the production of nanoparticles typically ranging between 10 and 100 nm. Several studies have demonstrated up to 80% yield improvement when using optimized extracts from plants like Azadirachta indica and Ocimum sanctum. The review outlines recent progress, including the use of novel botanical sources, advanced synthesis strategies, and comparative evaluations of plant extract efficiency. Key applications are discussed across medicine (e.g., targeted drug delivery and antimicrobial therapy), environmental cleanup (e.g., 90% dye degradation within 2 hours), and agriculture (e.g., 30% increase in crop yield via nano-fertilizers). Despite promising outcomes, issues such as scalability, reproducibility, and regulatory inconsistencies persist. The review underscores the potential of plant-mediated nanoparticle synthesis for advancing sustainable technologies and emphasizes the need for standardized methodologies and collaborative research to support its broader implementation.