Ultrafast Detection of Sulfur Dioxide Derivatives by a Distinctive Dual-Positive-Ion Platform that Features a Doubly Activated but Irreversible Michael Addition Site

Sulfur dioxide (SO2) is a gaseous signaling molecule and widely used as a preservative for foods, but its excessive intake is closely related to a series of diseases. Therefore, the development of a potent fluorescence probe for the detection of SO2 in foods and biological systems is of great significance. Herein, we report for the first time a dual-positive-ion platform-based fluorescence probe CMQ, designed by a doubly activated but irreversible strategy, which results in its ultrafast response to SO2 within 5 s in pure aqueous solution together with a low detection limit as 15.6 nM. In addition, the probe was successfully applied for imaging of SO2 in mitochondria of living cells and zebrafish and prepared as a reagent kit for convenient and instantaneous quantification of HSO3- in real food samples.

Automated summary

A highly efficient fluorescence probe CMQ was developed for the detection of sulfur dioxide in foods and biological systems, showing ultrafast response and low detection limit. Additionally, it was successfully applied for imaging in living cells and zebrafish.