Colorimetric and fluorescent sensor for selective sensing of Hg2+ ions in semi aqueous medium

A highly sensitive and selective detection of Hg2+ ion with simple salophen probe was developed. In DMSO: water (40:60, v/v) solution, Hg2+ ions coordinate with imine and shows color turn-off from yellow to colorless. Receptor 1 showed its ability for sensing Hg2+ cations sensitively through three channels: colorimetric, UV–vis and fluorescence spectroscopy. Hg2+ ions coordinate to the imine (Receptor 1) through NONO binding site forming 1:1 complex. It exhibits fluorescent ʹTurn-onʹ behavior based on solvent polarity. The detection limit of our receptor with mercury is 1 μg L−1.