Novel thiomaleimide-based fluorescent probe with aggregation-induced emission for detecting H₂S

It has been well established that Hydrogen sulfide (H₂S) is involved in various pathophysiological processes. Therefore, accurate monitoring H₂S levels in vitro or vivo is of great significance in biological systems. Herein, we firstly developed a thiomaleimide-based compound MAL-1 bearing aggregation-induced emission characteristic for selective response toward H₂S due to its nucleophilicity. The proposed sensor presented prominent sensitivity and selectivity with low detection limit of 75 nM and pseudo-first-order reaction rate constant of 9.65 × 10^-2 s^-1, as well as low cytotoxicity which works well in recognizing H₂S in real samples and visualizing H₂S in living cells. Thus, it could be concluded that the novel thiomaleimide-based probe would be a promising tool for assessing intracellular H₂S levels.