A novel FRET-based fluorescent probe for the selective detection of hydrogen sulfide (HS) and its application for bioimaging.

Hydrogen sulfide (HS) is an endogenously produced gaseous signaling molecule with multiple functions in many physiological and pathological processes. Herein, our group developed a novel fluorescent probe (Flu-N) for HS on the basis of the 7-amino-4-methylcoumarin and fluorescein FRET system. Adding HS to a solution of Flu-N resulted in a clearly observable fluorescence enhancement (50-fold). This probe showed high sensitivity and selectivity towards HS over other reactive species with a detection limit of 0.031 μM and a fast response time (within 8 s). Moreover, Flu-N displayed little toxicity to HepG-2 cells and was successfully applied to image exogenous and endogenous HS in living cells and nude mice.