Nobel Metal Quantum Dots for Nanomedicine

Abstract

Nanotechnology has revolutionised biomedical applications, particularly in the development of biosensors and diagnostic platforms. This study investigated the fluorescence properties of bovine serum albumin - encapsulated gold nanoclusters (BSA-AuNCs) in combination with surface-modified gold nanorods (GNRs), focusing on the role of mercaptohexanoic acid (MHA) and cetyltrimethylammonium bromide (CTAB) coatings. Ultraviolet – visible (UV Vis) spectroscopy was employed to confirm the synthesis and monitor the interaction between BSA-AuNCs and GNRs. Fluorescence intensity and lifetime measurements revealed distinct quenching behaviours, with GNR–CTAB exhibiting stronger quenching compared to GNR MHA. This was attributed to differences in surface chemistry and protein corona formation. The study demonstrated time-dependent fluorescence quenching and energy transfer mechanisms, highlighting the sensitivity of BSA-AuNC emission properties to nanorod surface functionalisation. Fluorescence lifetime analysis further validated the interaction with GNR CTAB, leading to a pronounced reduction in lifetime due to enhanced energy transfer. These findings underscore the importance of surface modifications in tuning optical properties and offer valuable insights for designing advanced biosensing systems. This work provides a framework for understanding protein–nanomaterial interactions and paves the way for the rational development of nanoparticle-based diagnostics and therapeutic platforms.