LAUSR

Gold nanoclusters are used as excellent scaffolds for the development of chemical and biological sensors due to their outstanding physical and chemical properties. In this study, a facile and green method has been employed for the preparation of highly fluorescent Au NCs by simply heating the gold precursor solution in the presence of a specially designed multidentate polymer ligand PTMP–PMAA. Herein, PTMP–PMAA functions as a reducing agent as well as a protecting agent. The Au NCs were characterized by fluorescence spectroscopy, ultraviolet absorption spectroscopy, dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF), and powder X-ray diffraction (PXRD) and were found to exhibit yellow fluorescence (λem = 553 nm), a high quantum yield (22.6%), excellent stability and water-solubility. Based on aggregation-induced fluorescence quenching, the Au NCs@PTMP–PMAA fluorescent NCs were used for the detection of Fe3+ with an acceptable sensitivity having a detection limit of 3.0 μM and high selectivity. Moreover, Au NCs were also explored for the fluorescence imaging of Fe3+ in living H9c2 cardiac muscle cells presenting internalization with green fluorescence from the cells, suggesting their potential applicability as bioimaging agents.