Spectroscopic study of the recognition of 2-quinolinone derivative on mercury ion.

A new compound based on 2-quinolinone derivative with very little side effects on organisms, 3-(1H-benzo[d]imidazol-2-yl)-6,7-difluoroquinolin-2(1H)-one, has been designed, synthesized and characterized. And its recognition ability was firstly studied by spectroscopy. The result indicated that the compound shows high selectivity for Hg2+ over other metal ions with detectable fluorescent signals in aqueous-methanol media. The proposed mechanism is that the fluorescence of the probe was quenched due to the effect from spin-orbit coupling of Hg2+ after the probe coordinated with Hg2+, and was proved by ESI-MS and 1H NMR analysis.