A biocompatible fluorescent probe for endogenous hydrogen sulfide detection and imaging.

Hydrogen sulfide (HS) acts as a messenger molecule and can mediate a variety of physiological functions. Conventional methods are seldom used to detect endogenous HS and present some difficulties in selective and accurate detection. Reaction-based recognition of endogenous HS by organic small molecule probes with good specificity and biocompatibility. To address this challenge, we developed a novel HS fluorescent probe 4-(2-(6-hydroxy-2-naphthyl) ethyl)-1-methylpyridinium (DSNP) that triggers a thiolysis reaction through a strong electron withdrawing group, releasing a fluorescent molecule. The simple probe DSNP not only have good selectivity, large Stokes shifts and biocompatibility, but also demonstrated a detection limit as low as 28.4 nM and reaction times as quick as 30 min. Moreover, it has been successfully applied to imaging intracellular HS in myeloma cells and zebrafish. This study opens new insights to help push this probe forward for its applicability for detailed HS localization studies in osteosarcoma.