Mechanistic Insights into Biogenic Multifunctional Metal-Based Nanoparticles: Biological Strategies and Biomedical Applications

Biogenically synthesized metal-based nanoparticles have emerged as an attractive alternative to traditional physicochemical methods. The conventional way to prepare metal nanoparticles involves using toxic chemicals as reducing agents and stabilizers, which is tedious to handle and highly detrimental to the environment. Hence, biological synthetic routes for the biosynthesis of metal nanoparticles have been widely explored in recent research. It involves using biological molecules present in organisms, such as bacteria, plants, and fungi, as well as vitamins and enzymes, to reduce, stabilize, and regulate nanoparticle growth. These green-synthesized nanoparticles have demonstrated promising biomedical applications, especially as antibacterial, anticancer, anti-inflammatory, and neuroprotective agents, owing to their superior biocompatibility and surface chemistry. In addition, there is potential to develop therapeutic formulations that leverage the interactions between nanoparticles’ properties and biological systems. This review discusses the mechanisms of biogenic synthetic routes, with a detailed discussion of plant, bacterial, enzymatic, fungal, and vitamin-mediated green synthetic metal-based nanoparticles and their applications in biomedical and drug delivery fields.