A rhodanine-based fluorescent chemosensor for sensing Zn2+ and Cd2+: Applications to water sample and cell imaging

Abstract

A rhodanine-based chemosensor RDV, ((E)-3-((2-hydroxy-3-methoxybenzylidene)amino)-2-thioxothiazolidin-4-one), was designed and synthesized. Compound RDV displayed selectivity to Zn2+ and Cd2+ through marked fluorescence increase in aqueous media. Importantly, cysteine was used for distinguishing RDV-Zn2+ and RDV-Cd2+. RDV had low detection limits (1.07 mu M for Zn2+ and 1.37 mu M for Cd2+). RDV proved to be a practical sensor to water sample analyses and cell imaging. The sensing mechanisms of RDV to Zn2+ and Cd2+ were illustrated by ESI-mass, fluorescence, FT-IR, UV-visible spectroscopy and theoretical calculations.