A dual-responsive fluorescent probe based on cyanine and naphthalimide units for detecting HClO and H₂S in living...

Hypochlorous acid (HClO) and hydrogen sulfide (H₂S) play very important roles in both physiological and pathological processes, however, the methods for simultaneously detecting HClO and H₂S were rarely reported. Here, a dual-responsive fluorescent probe (CyNa-N₃) based on cyanine and naphthalimide dyes was synthesized and investigated. The fluorescence probe showed better sensitivity, high selectivity response to HClO and H₂S by red emission and green emission bands, and the limits of detection were 0.17 µM and 0.15 µM respectively. MS (Mass Spectrum) and ¹H NMR (Nuclear Magnetic Resonance) confirmed the sensing mechanism of CyNa-N₃ detected HClO and H₂S, the calculation of density functional theory (DFT) further explained the internal mechanism of spectral change of CyNa-N₃. Moreover, CyNa-N₃ was successfully applied to image HClO and H₂S in living cells, which is beneficial for more efficient application in biological imaging.