A pyrene-thiophene based fluorescent probe for ratiometric sensing of bisulfite and its application in vivo imaging

A novel ratiometric fluorescent probe was designed and synthesized for detection of bisulfite, via pyrene as an electron donor (D) and 4, 5-dibromothiophene as an electron acceptor (A). It had good selectivity, sensitivity and short response time. The fluorescence intensity ratio at 420 nm and 530 nm (I-420/I-530) displayed a good linear relationship with the concentration of HSO3- in the range of 0-35 mu M, and the detection limit was 0.77 mu M. The possible recognition mechanism of probe and HSO3- was illustrated by NMR, HRMS and computational analysis. Notably, the probe was successfully applied for imaging HSO3- in A549 cells, Caenorhabditis elegans and zebrafish, which indicated that this probe had great potential for HSO3- detection in vivo.