Development of green to near-infrared turn-on fluorescent probes for the multicolour imaging of nitroxyl in living systems

Abstract

Nitroxyl (HNO) is one of the important reactive nitrogen species (RNS) and show significant biological activities with significant therapeutic potential. Herein, three novel turn-on probes (NP-1–3) based on structurally related dyes with different emission colors as fluorescent scaffolds have been developed for detecting HNO in biological systems. The probes exhibit high sensitivity, excellent selectivity, desirable performance at physiological pH and low cytotoxicity. By incubating living cells with these probes simultaneously, we demonstrate the multicolor imaging of HNO with emission colors in the range of green to near-infrared (NIR) in living systems for the first time. Furthermore, probe NP-3 responds to HNO with a significant turn-on NIR fluorescence signal upon excitation in the NIR region, and it is successfully applied for sensing HNO in living mice.