Cysteamine-capped copper nanoclusters as a highly selective turn-on fluorescent assay for the detection of aluminum ions.

A new type of copper nanoclusters was synthesized by a one-pot reaction using cysteamine as a capping agent and reducing agent (Cys-CuNCs). The synthesized CuNCs exhibited a spherical shape and a monodisperse and strong fluorescent emission characteristic peak at 430nm when exciting at 330nm. The Cys-CuNCs were demonstrated as a fluorescent chemodosimeter for the selective detection of Al3+. In the presence of Al3+, the fluorescent emission of the Cys-CuNCs was considerably enhanced, while other studied metal ions did not show this phenomenon. The fluorescent intensity near 380nm linearly increased with an increasing Al3+ concentration. The proposed method provided a working range of 1-7µM with a low detection limit of 26.7nM and was applied to determine Al3+ in drinking water samples with satisfactory results.