Abstract

A new ratiometric fluorescence probe E1 based on an excited-state intramolecular proton transfer (ESIPT) mechanism for detection of hydrogen sulfide (H2S) is reported. E1 responds to H2S quickly and showed a 30-fold fluorescence enhancement in 2 minutes. Moreover, E1 can detect H2S quantitatively with a detection limit as low as 0.12 μM in aqueous solution. Its potential for biological applications was confirmed by employing it for fluorescence imaging of H2S in living cells.