Cyanine-based NIR fluorescent probe for monitoring H2S and imaging in living cells and in vivo

Abstract As a critical gaseous signaling molecule, H 2 S is involved in various biological processes. To deeper study the physiological and pathological roles of H 2 S, convenient and efficient detection techniques for endogenous H 2 S in vivo are still in urgent demand. Herein, we reported a new turn-on Near-infrared (NIR) fluorescence probe NIR-H 2 S based on thiolysis reactions for detection of H 2 S. The probe possessed many excellent properties including high sensitivity and selectivity, good cell-membrane permeability, and low cytotoxicity. In vitro, NIR-H 2 S showed a 58-fold fluorescence enhancement when reacted with H 2 S in a buffer and displayed a good linear relationship ( r  = 0.9925) in a rather wide concentration range of H 2 S (0–500 μM). Furthermore, NIR-H 2 S was successfully employed in monitoring endogenous H 2 S induced by D -Cys in living cancer cells and mice. These results indicated that NIR-H 2 S had great potentiality in detecting cellular H 2 S in living animals and being applied to cancer diagnosis.