Computational insights into quetiapine adsorption on coinage metal nanoclusters: mechanistic basis for sensing and nanomedicine

Understanding how therapeutic molecules interact with metallic nanostructures is critical for advancing nanoscale sensing and drug-delivery technologies. In this work, we present a comprehensive density functional theory (DFT) investigation of a typical antipsychotic drug quetiapine (QTE) interacting with coinage metal nanoclusters (Au3, Ag3, and Cu3). Various adsorption configurations were analyzed to identify the most favorable sites and their influence on structural, electronic, and spectroscopic properties. Adsorption through the nitrogen center of QTE was found to be the most stable, showing significant charge transfer and orbital hybridization, particularly in the Cu3-QTE complex. These interactions markedly modify the HOMO-LUMO gap, dipole moment, and charge distribution, suggesting improved electronic reactivity and enhanced sensing response. Electron localization function (ELF), localized orbital locator (LOL), and reduced density gradient (RDG) analyses reveal the nature and strength of non-covalent interactions, while atoms-in-molecules (AIM) topology confirms bonding characteristics at the interface. Simulated UV-Vis and Raman spectra display red shifts and SERS-like enhancement consistent with experimental detection mechanisms. Collectively, this study establishes a fundamental framework for understanding metal-drug interactions at the quantum level and offers design insights for developing efficient biosensors and nanomedical devices based on coinage metal nanoclusters.