Highly selective and sensitive Hg2+ fluorescent sensors based on a phosphane sulfide derivative

Abstract

A series of fluorescent sensor molecules based on a phosphane sulfide derivative were designed and synthesized. The effect of the distance between the complex entities as well as the number and the length of fluorophores was investigated using both steady-state and time-resolved fluorescence methods. The complexation behavior of these sensor molecules, which have a distinct affinity for Hg(2+), is reported. The coordination of Hg(2+) induces a photoinduced electron transfer from fluorophore to the complexed mercury and results in a significant decrease of the fluorescence. Theses sensors exhibit very low detection limits in CH(3)CN/H(2)O (80/20 v:v) and excellent sensitivity to Hg(2+) over other potentially interfering cations such as Na(+), K(+), Mg(2+), Ca(2+), Cu(2+), Ag(+), Zn(2+), Cd(2+) and Pb(2+).