β-Carboline-functionalized dithioacetal as Hg2+-selective fluorescence probe in water

•A water-soluble fluorescence probe has been designed and synthesized.•The probe was highly effective for the detection and discrimination of Hg2+.•β-Carboline as a fluorophore is significant for the design of novel probes.

A novel sensing system based on the β-carboline core has been designed and synthesized for Hg2+ detection in water. We have demonstrated that a straight forward methodology can provide rapid, sensitive and selective recognition (cross-contamination experiments) for Hg2+ over a wide pH range. The vivid fluorescence change from blue to colorless can be clearly discriminated by the naked eye. Furthermore, there is a good negative correlation between the fluorescent intensity and the concentration of Hg2+ in the range 1.0 × 10−6 M–7.0 × 10−6 M. β-Carboline as a fluorophore synthesized via this route also provides a new strategy for the design of novel fluorescence probes and fluorochromes.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide