A highly sensitive and responsive fluorescent probe based on 6-azide-chroman dye for detection and imaging of hydrogen sulfide in cells.

Hydrogen sulfide or H2S is known as an important gasotransmitter involved in regulation of many physiological and pathological processes. Since a small amount of H2S is produced by endogenous cells in the body and microorganisms in the gastrointestinal tract (GI tract), the current detection probes are limited for their use in measurement of unpretentious change of H2S level both in vitro and in vivo. Therefore, development of a highly sensitive and responsive fluorescent probe for measurement of H2S in vivo is of great significance for investigation of H2S function and toxicity. Here, we designed a novel fluorescent probe AC-N3 through introducing azide in 6-position of chroman dye based on the hypothesis that 6-position (para-position) of chromone may be a potential trigger of fluorescent properties. The probe AC-N3 exhibits a better selectivity without interference from analytes, high sensitivity and little cytotoxicity. In addition, we confirmed that the conversion of electron-donating group in 6-position of chromone can trigger the change of fluorescence, which can be applied to design of other fluorescent probes.