A ratiometric AIE probe for visual discrimination monitoring of hydrogen sulfide and biogenic amines by different sensing mechanism and its application in cells, tumor model and food.

Hydrogen sulfide (H2S) and biogenic amines (BAs) are naturally generated from foods that adversely affect human health. The very close structural similarities between cysteine and homocysteine present a great challenge to achieve their selective detection using regular fluorescent probes, limiting the biological and pathological studies of these two amino thiols. In this work, we have developed a novel ratiometric AIE probe named MTMC for the visual discrimination detection of H2S and BAs. Probe MTMC displayed a remarkable fluorescence color change after the addition of H2S (from red to yellow) and BAs (from red to green), suggesting that MTMC can identify two analytes with the naked eye. Also, NMR, HRMS and DFT calculation confirmed the different sensing mechanism of probe MTMC for H2S and BAs. Also, we successfully prepared MTMC test strips and was applied for real-time monitoring of H2S gas and BAs gas released during food spoilage. Importantly, MTMC demonstrated the ability in the detection of H2S in living cells by ratiometric fluorescence singal and effectively accumulate in the tumor region and could as a powerful tool in early clinical diagnosis.