Gold nanoclusters (Au NCs), as an emerging class of luminescent materials, hold great promise for diverse applications. However, their low near-infrared (NIR) luminescence quantum yields (QYs) have limited their bioimaging application. Herein, we present a novel strategy to enhance the luminescence, stability, and antiprotein adsorption of Au NCs through charge complementarity of ligands. Specifically, we designed Au-ODPCA NCs with zwitterionic ligands achieving a remarkably high NIR-II (1050 nm) QY of 3.8%. Through systematic study, we demonstrated that the emission enhancement originated from the charge complementarity of ligands, which increases the rigidity of the Au-ligand complex, thereby boosting the emission. The zwitterionic ligand-capped Au NCs not only exhibited enhanced NIR-II luminescence but also demonstrated excellent antiprotein adsorption properties, allowing for acute kidney injury (AKI) diagnosis and sentinel lymph node imaging.
Li et al. (Mon,) studied this question.