A novel NIR fluorescent probe for the double-site and ratiometric detection of SO derivatives and its applications

A feasible double-site near-infrared (NIR) fluorescent probe Q5 based on xanthenes was developed. Probe Q5 showed clearly HSO 3 induced changes in the fluorescence ratio of two well-separated NIR and VIS peaks, showing excellent selectivity compared with other analytes. And the detection limit of the probe for HSO 3 was found to be 89 nM. Furthermore, fluorescence imaging experiments of HSO 3 in CEM cells revealed that the probe has potential application value in biological systems. A naked-eye fluorescent probe based on xanthenes was obtained.