Abstract
Metallic nanoparticles have gained considerable attention in pharmaceutical and biomedical research because of their high surface area, tunable size, and unique optical, catalytic, magnetic, and antimicrobial properties. This review provides an overview of nanotechnology, highlighting both conventional and green synthesis approaches, the major types of metallic nanoparticles, and their applications in healthcare. Conventional methods, including top-down and bottom-up strategies, chemical reduction, sol-gel, hydrothermal, electrochemical, microwave-assisted synthesis, and laser ablation, enable precise control over nanoparticle characteristics but often involve hazardous chemicals and high energy consumption. In contrast, green synthesis employs biological resources such as plants, bacteria, fungi, algae, and natural biomolecules to produce nanoparticles in a more sustainable and eco-friendly manner. The review also discusses the pharmaceutical roles of gold, silver, copper, zinc oxide,