Fluorescent sensors for Hg 2+ based on rhodamine derivatives

Abstract

A series of rhodamine-based chemsensors ( RC1– 4) were designed by introducing different frameworks, and their sensing behavior toward metal ions was investigated by fluorescence spectroscopy. RC1 and RC2 achieved excellent selectivity to Hg 2+ exploiting guest-induced structure transform mechanism, and showed a sharp Hg 2+-selective fluorescence enhancement response in aqueous system under physiological pH value and possesses high selectivity against the background of environmentally and biologically relevant metal ions including Li +, Na +, K +, Ca 2+, Mg 2+, Ba 2+, Co 2+, Ni 2+, Cu 2+, Zn 2+, Pb 2+, Cd 2+, Fe 3+and Al 3+.