Highly fluorescent au nanoclusters: Electrostatically induced phase transfer synthesis for Cu(2)(+) sensing.

This paper reports a convenient method for the synthesis of highly fluorescent Au nanoclusters (NCs) via electrostatically induced phase transfer. Furthermore, on the basis of an aggregation-induced fluorescence quenching mechanism, the potential application for Cu(2)(+) sensing on the fluorescence emission of the Au NCs is discussed. These prepared fluorescent Au NCs offer acceptable sensitivity, high selectivity, and a limit of quantitation of 0.02 μM for the measurement of Cu(2)(+) , which is lower than the maximum level (1 ppm, equals to 15.6 μM) of Cu(2)(+) permitted in drinking water in China. This study contributes to the further development of practical applications with fluorescent NCs.