Reversible Fluorescent Probe for Selective Detection and Cell Imaging of Oxidative Stress Indicator Bisulfite

In this paper, we report a benzothiazole-functionalized cyanine fluorescence probe and demonstrate that it is selectively reactive to bisulfite, an intermediate indicator for oxidative stress. The selective reaction can be monitored by distinct ratiometric fluorescence variation favorable for cell imaging and visualization. The original probe can be regenerated in high yield through the elimination of bisulfite from the product by peroxides such as hydrogen peroxide, accompanied by fluorescence turning on at 590 nm, showing a potential application for the detection of peroxides. We successfully applied this probe for fluorescence imaging of bisulfite in cancer cells (MCF-7) treated with bisulfite and hydrogen peroxide as well as a selective detection limit of 0.34 μM bisulfite in aqueous solution.