A New Dual-response Behavior Chemosensor Based on 2-(1H-dithienobenzoimidazole)-pyridine Unit for Hg2+ Detection

Abstract

A novel chemosensor has been synthesized by using 2-(1H-dithienobenzoimidazole) pyridine (DBP) as a receptor unit. The compound was highly selective towards Hg 2+ with significant absorption change, which could be easily seen by 'naked-eye'. Moreover, it showed highly sensitive towards Hg 2+ with obvious fluorescence change from bright blue to dark in methanol. The limit of detection for Hg 2+ detection is determined to be 3.17 × 10 -8 mol L -1 according to fluorescence titration, and the stoichiometry between DBP and Hg 2+ is calculated to be 1:1. Therefore, the DBP could be used as a potential candidate 'naked-eye' colorimetric sensor or a "turn off" fluorescence probe for Hg 2+ detection.