A chromene based fluorescence probe: Accurate detection of peroxynitrite in mitochondria, not elsewhere

Abstract

• A novel fluorescent probe was synthesized for the detection of ONOO − by conjugating dicyano-vinyl with benzopyran-chromone. • The probe shows specifically selectivity over other biologically relevant ROS/RNS/RSS. • The sensing mechanism is the cleavage of the carbon-carbon double bond by the nucleophilicity and oxidation of peroxynitrite. • The probe has a certain mitochondrial targeting and localization effect. • BC-PN-2 can accurately identify ONOO − in mitochondria by imaging of exogenous ONOO − in HepG2 cells. A novel fluorescent probe (BC-PN-2) for the detection of ONOO − was synthesized by conjugating dicyano-vinyl with benzopyran-chromone. The dicyano-vinyl group can be destructed by ONOO − to generate an aldehyde group resulting in strong fluorescence. Compared with the general fluorescence probes, a novel reactive site to detect ONOO − in mitochondria is used in this probe and the results show short response time, high sensitivity and excellent selectivity toward ONOO − among reactive oxygen species (ROS) and reactive nitrogen species (RNS) in PBS. Subsequent fluorescence imaging shows the high membrane permeability, a certain mitochondrial targeting and localization effect of the probe. In addition, the product BC-aldehyde cannot permeate through the membrane. Meanwhile, BC-PN-2 can accurately identify ONOO − in mitochondria by imaging of exogenous ONOO − in HepG2 cells and prove detected ONOO − are from mitochondria.