A Novel Colorimetric Fluorescent Probe for SO2 and Its Application in Living Cells Imaging

A novel chromenylium-based fluorescent probe was exploited for sulphur dioxide (SO2) detecting. The probe displayed a remarkable fluorescence turn-on response towards SO2based on the nucleophilic addition reaction to the carbon-carbon double bond with 105 nm Stock shift. The probe was successfully applied for the quantification of SO2.The linear detection range was from 0–160 μM with the detection limit as low as 99.27 nM. It also exhibited high selectivity for SO2than other reactive species and amino acids. Furthermore, cell staining experiments indicated that the probe was cell membrane permeable and could be used for high-performance imaging of SO2in living cells. The superior properties of the probe made it highly promising for use in chemical and biological applications.