Monitoring of Hydrogen Polysulfide a NIR-Excitable Reversible Fluorescent Probe Based on Upconversion Luminescence Resonance Energy Transfer.

Hydrogen polysulfide (HS), derived from hydrogen sulfide (HS), has attracted increasing attention, which is suggested to be the actual signal molecule instead of HS in physiological and pathological processes. Reversible detection of HS through a NIR-excitable fluorescence probe is an effective means to understand its functions but is quite challenging. Herein, we reported a NIR-excitable ratiometric nanoprobe for the reversible detection of HS based on luminescence resonance energy transfer principle with upconversion nanoparticles as the energy donor and an organic molecule, SiR1, as the energy acceptor and reversible recognition unit of HS. The as-prepared nanoprobe exhibited high selectivity and fast response for the reversible detection of HS, which can monitor the formation and consumption of endogenous HS in living cells. Because of the reduced autofluorescence by NIR excitation, it was successfully applied for tracking the fluctuation of HS concentration of mice in physiological and pathological processes including inflammation and liver injury.