Synthesis of a NIR fluorescent dye and its application for rapid detection of HSO3− in living cells.

SO 2 and its derivatives (HSO 3 −, SO 3 2−) play a significant important role in many industries and organisms. Based on coumarin and benzopyranose, a promising NIR ratiometric fluorescent probe BAOA (11-oxo-2,2′,3,3′,6,7,7′,8′-octahydro -1H,1′H,5H,6′H,11H- [10,12′-bipyrano [2,3-f] pyrido [3,2,1-ij] quinolin]-13′-ium perchlorate) was designed and developed to detect HSO 3 − rapidly and sensitively. The sensing mechanism was Michael addition reaction, in which, strongly nucleophilic HSO 3 − attacked carbon-carbon double bonds and BAOA-HSO 3 was formed. A superior linear calibration curve between the fluorescence ratio I 490 /I 722 and concentrations of HSO 3 − was obtained in the range of 1.25–8.75 μmol/L and the LOD was figured out as 63.0 nmol/L. Cell experiments showed that BAOA could not only locate mitochondria, lysosomes, ER and Golgi but also detect exogenous HSO 3 − in living cells. A promising NIR ratiometric fluorescent probe for HSO 3 − was designed, which sensing mechanism was nucleophilic HSO 3 − attacking carbon-carbon double bonds resulting from Michael addition reaction. [Display omitted] [ABSTRACT FROM AUTHOR]