An isophorone-based far-red emitting ratiometric fluorescent probe for selective sensing and imaging of polysulfides.

Recent studies have shown that as members of the reactive sulfur species family and the oxidized forms of HS, hydrogen polysulfides (HS) play important roles in physiological and pathological processes. Therefore, accurate detection of HS levels in living systems is of great significance. In this study, we report an isophorone-based far-red emitting fluorescent probe (RPHS1) for selective ratiometric sensing and imaging of HS. RPHS1 shows specific ratiometric response towards HS with fast reaction rate and low detection limit in aqueous media. Furthermore, confocal fluorescence microscopy experiments demonstrate that RPHS1 can be applied for HS imaging in living cells.