A novel fluorescent probe based on naphthimide for H₂S identification and application

In view of the superior chemical activity of selenoether bond (-Se-) and the excellent optical properties of naphthimide, a novel fluorescent probe (NapSe) with near-rectangular structure, which contains double naphthimide fluorophores linked by selenoether bond, is designed for specific fluorescence detection of hydrogen sulfide (H₂S). NapSe has excellent optical properties: super large Stokes Shift (190 nm) and good stability in a wide pH range. The selectivity of NapSe fluorescence detection of H₂S is high, and displays excellent "turn-on" phenomenon and strong anti-interference. And the fluorescence intensity increased obviously, reaching 42 times. The time response of probe NapSe is very rapid (3 min) compared with other fluorescence probes that respond to H₂S. It shows high sensitivity by calculating the detection limit (LOD) as low as 5.4 μM. Notably, the identification of H₂S by probe NapSe has been successfully applied to the detection of test paper and the detection of exogenous and endogenous fluorescence imaging of MCF-7 breast cancer cells.