An aza-coumarin-hemicyanine based near-infrared fluorescent probe for rapid, colorimetric and ratiometric detection of bisulfite in food and living cells

A novel aza-coumarin-hemicyanine conjugated hybrid was prepared, which was found to be a promising colorimetric and ratiometric near-infrared (NIR) fluorescent probe for detection of bisulfite/sulfite in aqueous solution. This probe shows a rapid response (within 30 s) and high selectivity and sensitivity for bisulfite/sulfite, giving distinct colorimetric and ratiometric fluorescence changes at 717 and 560 nm. The detection limit for bisulfite was estimated to be 87 nM. In addition, detection of bisulfite in food samples and bioimaging of both exogenous and endogenous bisulfite in living cells with this probe were successfully applied, which indicates that this probe holds great potential for bisulfite detection both in real samples and in living cells.