A comprehensive overview of fabrication of biogenic multifunctional metal/metal oxide nanoparticles and applications

Abstract The re-evaluation of animals, plants, and microorganisms for green synthesis has revolutionized the fabrication of metallic nanoparticles (MNPs). Green synthesis provides more biocompatibility compared to chemically synthesized MNPs, which make them ideal for diverse biological applications, especially in biomedicine. Various organisms have been extensively studied for green synthesis. Interestingly, angiosperms, algae, and animal-derived biomaterials like chitin and silk have shown a prominent role in synthesizing these nanoparticles. Moreover, bacteria, viruses, and fungi serve as sources of reducing agents, further expanding green synthesis possibilities. Despite progress, research on natural reducing agents remains relatively limited, with only a few exceptions such as tea and neem plants receiving attention. Green-synthesized nanoparticles have diverse applications in various fields. In biomedicine, they enable drug delivery, targeted therapies, and bio-imaging due to their enhanced biocompatibility. Some MNPs also exhibit potent antimicrobial properties, aiding in disease control and eco-friendly disinfection. Furthermore, green nanoparticles contribute to environmental remediation by purifying water and serve as sensitive biosensors for diagnostics and environmental monitoring. This review will provide the recent progress and advancements in the field of green synthesis (GS) of nanoparticles. It will also analyze the key characteristics and evaluate the advantages and disadvantages of GS compared to chemical synthesis.