A super-fast response fluorescent probe for detecting endogenous H2S in living cells

Endogenous hydrogen sulfide (H2S) has been acknowledged as the third gasotransmitter and is closely related to human health and diseases. In this study, we describe a near-infrared fluorescent probe 2-(2-(4-(7-nitrobenzo[c] [1,2,5] oxadiazol-4-yl)oxy)styryl)-4H-chromen-4-ylidene) malononitrile (DCM-NBD) that employs (2-(4-hydroxystyryl)-4H-chromen-4-ylidene) malononitrile (DCM-OH) as a fluorophore and 7-nitro-1,2,3-benzoxadiazole (NBD) as a recognition group. This probe, DCM-NBD, shows super-fast response to H2S as compared to other current probes, which is important to monitor the dynamic and transient state of H2S in a biological system. In addition, a large Stokes' shift (120 nm) and near-infrared emission (690 nm) of DCM-NBD is suitable for biological imaging. DCM-NBD has the potential to elucidate the biological function of H2S in the biosystem.