Fluorescent probes based on an oxonium-coumarin scaffold for the detection of SO2 derivatives

Abstract

In this work, a pair of fluorescent probes CPO were designed for the detection of SO₂ derivatives based on the FRET principle. The acceptor part of the CPO probes is made of oxonium and the donor part is coumarin derivatives. Probe CPO1 has stable chemical properties and relatively outstanding optical properties, with ultra-fast response time (<30 s), excellent specificity ability, a 137 nm emission window gap, and mitochondrial targeting capability; it was used for cell experiments and prepared as fluorescent strips for the measurement of Na₂SO₃ concentrations in aqueous solutions. Probe CPO2 exhibits obvious variation in the fluorescence ratio in different solvents. Owing to the weak fluorescence of CPO2, compound CPO2 was not utilized for further experiments.