DefinePK

Abstract

Nanotechnology has emerged as a transformative field in medicine, enabling the design of nanoscale systems for diagnostics, imaging, and therapy. Among these, gold nanoparticles (AuNPs) have attracted significant attention owing to their tunable size (1–100 nm), inert nature, ease of synthesis, and unique optical properties that have been recognized since their use in ancient artwork. In recent years, AuNPs have demonstrated broad biomedical applications, including photothermal therapy, targeted drug delivery, antiviral strategies, early detection of cardiovascular disorders, cancer diagnosis, kidney disease monitoring, bioimaging, and biosensing. Their surfaces can be functionalized with peptides, antibodies, or polymers to achieve selective cellular targeting through mechanisms such as the enhanced permeability and retention (EPR) effect and receptor-mediated endocytosis. They can be used for other applications with different properties as well by changing the size and chemistry of the gold nanoparticles. The working of gold nanoparticles is first checked in vitro and then in vivo using animal models. Despite these advantages, challenges remain, including dose-dependent cytotoxicity, stability concerns, and regulatory barriers that limit large-scale clinical translation. Continued research focusing on surface modification, synthesis, and immune evasion strategies is expected to further expand the therapeutic and diagnostic potential of gold nanoparticles.