A HBT-based bifunctional fluorescent probe for the ratiometric detection of fluoride and sulphite in real samples.

Abstract

Based on a core of 2-(benzo[d]thiazol-2-yl)phenol (HBT), a bifunctional ratiometric fluorescent probe, HBT-FS, was constructed for the discriminative detection of fluoride (F-) and sulphite (SO32-) with high sensitivity and selectivity. HBT-FS itself displayed a green fluorescence with λEmmax = 498 nm. The treatment of HBT-FS with F- resulted in a red fluorescence (λEmmax = 634 nm) with a large Stokes shift and a 291-fold enhancement in the ratio of the fluorescence intensity (I634 nm/I498 nm). Upon the addition of SO32-, HBT-FS exhibited a blue fluorescence (λEmmax = 371 nm) and the ratiometric fluorescence enhancement was remarkable (9445 folds for I371 nm/I498 nm). HBT-FS was successfully used to qualitatively and quantitatively determine F- and SO32- in a ratiometric manner in real samples.