A Highly Selective Nir Fluorescent Probe for Hg2+ and its Multiple Application in Biological and Environmental Systems

Abstract

A novel near-infrared (NIR) fluorescent probe based on twisted intramolecular charge transfer (TICT) effect was designed and synthesized for establishing a sensitive method for detecting Hg2+. After the addition of Hg2+, the interaction between the probe and Hg2+ causes the thiocarbonate to fall off, resulting in a red shift of the absorption peak of the probe. The linear detection range of the probe for Hg2+ was 0-0.1 μM and the detection limit was 6.57 nM. This method had excellent selectivity, sensitivity and anti-interference ability in detecting Hg2+. In the real sample experiments, the recovery rate of the probe to Hg2+ was from 93.79% to 101.12% in the detection system made of different concentrations of Hg2+ in each water sample, indicating that the probe has corresponding research value in the field of environmental monitoring. Biological experiments had proved that the probe not only had low cytotoxicity, but also successfully achieved visual detection of Hg2+ in cells and zebrafish.

Keywords: Fluorescent probe, thiocarbonate, Hg2+, Near-infrared imaging, twisted intramolecular charge transfer