Dimethylamino naphthalene-based fluorescent probes for hydrogen sulfide detection and living cell imaging.

Hydrogen sulfide shows great importance in various physiological and biochemical processes. The development of fluorescence probes for facile and efficient detection of H2S has attracted increasing attention of researchers. Herein, we synthesized two fluorescence probes based on simple naphthalene structure for detection of H2S. Upon reaction with H2S, the probe DN-DM exhibited a red fluorescence emission with large Stokes shift. The probe showed high sensitivity, pH insensitivity and good selectivity for H2S over other analytes including common biothiols. The detection mechanism was based on the thiolysis of the dinitrophenyl ether moiety, which was confirmed by 1H NMR spectral analysis. The DFT calculation was also performed for a deeper understanding of the photophysical properties. In addition, these probes showed good cell-membrane permeability and could be utilized for detection of H2S in living cells.