AN INDOCYANINE-BASED TURN-ON FLUORESCENT PROBE FOR SPECIFIC DETECTION OF BIOTHIOLS

A novel heptamethine cyanine-based turn-on fluorescent probe Cy-DNBS was designed and synthesized, which was used successfully to detect biothiols with high selectivity and sensitivity. With the addition of biothiols, the probe displayed similar to 30-fold fluorescence enhancement at 625 nm. Meanwhile, the solution color changed remarkably from green to red, which provides a method to recognize biothiols by the 'naked eye'. The detection limit of Cys, GSH and Hcy are 2.24 nM, 1.99 nM and 4.46 nM, respectively.