A coumarin based fluorescent probe for rapidly distinguishing of hypochlorite and copper (II) ion in organisms

A dual-functional fluorescent probe based on coumarin fluorophore for monitoring ClO − and Cu 2+ was synthesized and characterized. The identification mechanisms for ClO − and Cu 2+ induced different colorimetric and ratiometric changes. ClO − caused a colorimetric change from yellow to colorless and 120 nm blue-shifted emission spectra from red to blue. Besides, Cu 2+ induced a remarkable fluorescence quenching behavior and 36 nm blue-shifted absorption spectra accompanied by the color change from yellow to luminous yellow. As expected, Probe 1 displayed excellent selectivity and sensitivity for detecting ClO − and Cu 2+ over other competing ions in their respective systems. The limits of detection for ClO − and Cu 2+ were 24.62 nM and 0.39 nM, respectively. The recognition mechanisms were proved by 1 H NMR, mass spectrum and theoretical calculations. More importantly, the reversibility of Cu 2+ could be applicable to rapid quantification for ClO − /Cu 2+ . Thus, the strategy for sensing ClO − /Cu 2+ was carried out, which revealed broad applications of Probe 1 in multiple actual water and biology.