Photoresponsive Gold Nanoparticles (AU-NPS) For Biomaterials

Photoresponsive gold nanoparticles (AuNPs) are smart nanomaterials that combine the plasmonic properties of gold with the reversible photochemistry of organic chromophores. Surface functionalization with photoactive molecules such as azobenzene, fluorescein, perylene, and pyrene enables light-controlled modulation of conformation, fluorescence, and surface interactions. These systems show strong potential in drug delivery, bioimaging, biosensing, and photothermal therapy. Recent advances in design, synthesis, and biomedical integration are discussed, along with challenges such as limited light penetration, photostability, and clinical scalability, and emerging prospects including NIR-responsive and multi-stimuli platforms.