A Novel NIR Fluorescent Probe for Rapid Response to Hydrogen Sulfide

Abstract Hydrogen sulfide (H₂S), as an important small molecule bioregulator, plays a key role in many physiological activities and signaling, and abnormal fluctuations in H₂S concentration can lead to a variety of diseases. Therefore, it is of great significance to develop a near-infrared fluorescence probe to visualize fluctuations in H₂S levels. This work is based on Sulfur-substituted dicyanomethylene-4H-chromene (DCM), A novel NIR fluorescent probe (E) -3 - (2 - (4 - (dicyanomethylene) -6-methyl-4H-Thiochromen-2-yl)vinyl-1-methylquinolin-1-ium (DMT) was synthesized successfully. Research has found that in weakly alkaline environments, the probe DMT reacts rapidly with H₂S (only 10 s), the fluorescence intensity at 684 nm is enhanced by about 60 fold, the detection limit is as low as 0.1623 µM, the Stokes shift is large (94 nm), and strong selectivity as well as anti-interference ability towards H₂S. This will provide a new method for the rapid detection and further application of H₂S.