A resorufin-based fluorescent probe for imaging polysulfides in living cells

Abstract

As the oxidative metabolites of the endogenous gasotransmitter H₂S, H₂S_n have attracted ever-increasing attention in the field of biomedical research due to their vital functions in biological systems. Herein, we report a resorufin-based “turn-on” probe for H₂S_n sensing. An S_NAr substitution–intramolecular cyclization cascade reaction was used in this probe for detecting exogenous and endogenous H₂S_n. The detection process could be monitored using UV-Vis and fluorescence spectroscopy and the naked eye. The emission response of the probe towards H₂S_n presented a good linear relationship in the 0–50 μM concentration range, and the LOD of this probe was 24 nM. The probe was used successfully to visualize endogenous H₂S_n generated in the RAW 246.7 cells under external stimulation.