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 (I420/I530) displayed a good linear relationship with the concentration of HSO3− in the range of 0–35 μM, and the detection limit was 0.77 μM. 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.