A new strategy for the fluorescence discrimination of Cys/Hcy and GSH/H2S simultaneously colorimetric detection for H2S.

The development of fluorescent probes enabling distinguishable detection Cys, Hcy, GSH and H2S is still a considerable challenge owing to their similar functional group with comparable reactivity. In this work, a novel fluorescent probe FHC-O-NBD has been synthesized, and a practicable strategy for the fluorescence discrimination of Cys/Hcy and GSH/H2S, especially the colorimetric detection for H2S have been presented. FHC-O-NBD reacted with Cys/Hcy to produce two fluorescent emissions at 486 nm and 550 nm, while for GSH/H2S, only one fluorescent signal at 486 nm appeared. And, only upon addition of H2S, the color of the system changed from colorless to pink. So it can serve as a colorimetric probe for H2S by "naked eye". Furthermore, FHC-O-NBD can selectively distinguish Cys/Hcy and GSH/H2S in living cells, meaning it has great potential in biological applications.