A long-acting cyclic and near-infrared fluorescent probe was synthesized for monitoring peroxynitrite (ONOO⁻). The fluorescence intensity at 652 nm rapidly changes in response to the sensing and eliminating processes for ONOO⁻. This is the first probe with multiple functions including real-time detection, long-acting monitoring and in-situ elimination, which helps to maintain the physiological balance of ONOO⁻.

Abstract

Two through-bond energy transfer fluorescent probes with a dihydroxyl naphthyl-pyrenyl conjugated system were synthesized for long-acting cyclic monitoring and eliminating peroxynitrite (ONOO⁻). The probes exhibit large Stokes shifts (230 or 280 nm) and the fluorescence at 620 or 652 nm rapidly change in response to continuously variable concentrations of ONOO⁻ under physiological conditions. The probes show good reversibility and can rapidly monitor the concentration changes of ONOO⁻ in real time. In addition, with the additions of the probes, the decomposition of ONOO⁻ is greatly accelerated. Therefore, the probes can effectively eliminate the excess ONOO⁻ as well as sensing it. The biological studies showed that the probes can effectively and reversibly eliminate both exogenous and endogenous ONOO⁻ in-situ as well as sensing its changes in cells, which can help to maintain the normal physiological concentration of ONOO⁻ in organisms. This is the first system that a probe achieves multifunction including real-time detection, long-acting cyclic monitoring and in-situ elimination, thereby maintaining a normal physiological balance for ONOO⁻.