Rational Development of Dual-Ratiometric Fluorescent Probes for Distinguishing between H₂S and SO₂ in Living Organisms

For better investigating the complicated relationships between H2S and SO2, simultaneously detecting and visualizing them with good selectivity is crucial. However, most sensing mechanisms for H2S and SO2 probes are based on the addition reactions with the double bonds, which have no selectivity. In this work, by introducing an active triple bond into 4-dicyanovinyl-7-diethylamino-coumarin, we construct two unique sensors for not only distinguishing between H2S and SO2 but also sensing H2S and SO2 in a dual-ratiometric manner. Moreover, the modified sensor was successfully applied in living cells and zebrafish for discriminating H2S and SO2.