Intramolecular Charge Transfer (ICT) Based Two-photon Fluorescent Probe for Bisulfite with Bioimaging Applications

Abstract

A two-photon fluorescent probe has been adopted for bisulfite based on an intramolecular charge transfer (ICT) mechanism. The fluorescence intensity of the probe decreased by 837 fold following treatment with HSO₃^? and the detection limit was 42?nM. This probe showed excellent properties such as high photostability, good two-photon properties, and large Stokes shifts. More importantly, this approach offers a rapid, highly selective, and sensitive method to determine HSO₃^? in buffer solutions and real samples. Furthermore, the probe was successfully used for two-photon fluorescence visualization of trace SO₂ derivatives in biological systems.