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

A novel sensing system based on the β-carboline core has been designed and synthesized for Hg(2+) detection in water. We have demonstrated that a straight forward methodology can provide rapid, sensitive and selective recognition (cross-contamination experiments) for Hg(2+) 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 Hg(2+) 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.