New carbazole fluorescent sensor for ultrasensitive and ratiometric sensing of SO2 derivatives and hydrazine

[Display omitted] •A novel bifunctional fluorescent probe CBTA was developed.•CBTA showed high sensitivity and selectivity to HSO3− and N2H4 in ultrafast time.•CBTA has low detection limits for bisulfite and hydrazine.•CBTA could visualize endogenous HSO3− in living cells. The probe CBTA is a novel bifunctional fluorescent probe that can detect bisulfite and hydrazine hydrate in a rational manner. And probe CBTA could specifically detect bisulfite and hydrazine hydrate among different analytes. Moreover, the response time of probe CBTA to SO2 derivatives and hydrazine is extremely short, and the detection limits for bisulfite and hydrazine are as low as 5.6 nmol and 39 nmol. Cellular experiments also indicated that the probe CBTA was low in cytotoxicity and could be applied to cellular fluorescence imaging. Therefore, the probe CBTA could provide an efficient means for detecting SO2 derivatives and hydrazine in vitro.