A label free Ag+ sensing method via in situ formation of metal coordination polymer

Metal ions sensing play critical roles in environmental monitoring and in biology. In this assay, we report the development of a facile fluorometric method for the sensing of Ag+ ions via the in situ formation of metal coordination polymer, based on the selective interactions of GSH with Ag+. The formation of coordination polymer with net multiple negative charges in an aqueous buffer solution (Tris-HAc, pH 9.0) resulted in aggregation and fluorescence quenching of a cationic perylene probe. The difference in emission intensity spurred us to develop a new strategy for sensing Ag+ ions. The proposed Ag+ detection method is simple, convenient, selective and sensitive, and can be used for Ag+ detection in lake water samples.