A highly efficient coumarin-based turn-on fluorescent probe for specific and sensitive detection of exogenous and endogenous Nitroxyl in vivo and in vitro

Nitroxyl (HNO) is documented to be closely concerned with diverse pathological and physiological processes within living organisms. This research showcased the creation of a smart fluorescent turn-on probe, CCA-HNO, which is based on coumarin. It is designed to specifically detect HNO in the presence of metal ions, anions, biothiols, and reactive oxygen species (ROS). The probe CCA-HNO exhibited low detection limit of 34 nM and wide pH applicable range of 2-12 in the detection process of HNO. In view of its low cytotoxicity and admirable cell permeability, the probe CCA-HNO was utilized for high-contrast imaging of exogenous and endogenous HNO fluctuations in living cells. Moreover, the probe CCA-HNO also can effectively realize the real-time visualization of exogenous and endogenous HNO in living zebrafish. We anticipated that this finding can provide an excellent method for knowing the biological function of HNO in relevant pathological processes.