Colorimetric and ratiometric fluorescent detection of bisulfite by a new HBT-hemicyanine hybrid

A novel HBT-hemicyanine hybrid was prepared. This hybrid not only displays a large red-shifted (Δλ = 125 nm) emission compared to the well known ESIPT dye HBT, but also can be used as a new probe for rapid, colorimetric and ratiometric fluorescent detection of bisulfite with high selectivity and sensitivity in aqueous solution. The detection limit of this probe for HSO3− was calculated to be about 56 nM with a linear range of 0–25 μM. The potential application of this probe was exampled by detection of bisulfite in real food samples and living cells. Overall, this work not only provided a new ratiometric sensing platform, but also provided a new promising colorimetric and ratiometric fluorescent probe for bisulfite. [Display omitted] •A new colorimetric and ratiometric fluorescent probe for bisulfite was reported.•This probe is based on a novel HBT-hemicyanine hybrid and shows high selectivity and sensitivity for bisulfite.•The probe can be used to quantitatively detect bisulfite in real food samples.•Fluorescent imaging of bisulfite in living cells by this probe was also successfully applied.