Design, Synthesis And Application Of Fluorescent Probes For The Detection Of Hydrogen Sulfide And Palladium Ions

Fluorescent probes, a kind of excellent detection tools, have the properties of good selectivity, high sensitivity, simple operation as well as low cost, which lead to the widely use of fluorescent probes in chemistry, medicine, biology, physics, materials science, environmental science and other fields. Fluorescent probes for the detection of hydrogen sulfide and palladium ions have been synthesized in this paper. The main work are as follows:(1) A novel fluorescent probe PI-H2S for the detection of hydrogen sulfide is developed, with the the derivative of phenanthroimidazole acting as the fluorophore and 2,4-dinitrophenyl ether as the sensitive recognition site for hydrogen sulfide. The fluorophore and probe are characterized by 1H NMR and mass spectra. The fluorescence spetra experiments revealed that the addition of H2S to the solution of probe PI-H2S leads to a large fluorescence enhancement. The probe exhibits good selectivity and high sensitivity toward hydrogen sulfide, with the detection limit being 1.12 μM. Moreover, the probe can be applied to detect hydrogen sulfide in wide pH range. The fluorescence imaging test demonstrated that the probe has good cell membrane permeability and can be applied to detect hydrogen sulfide in living cells.(2) A new probe named HF-Pd is synthesized for the detection of palladium ions. The fluorophore of the probe is the derivative of 3-hydroxyflavone, which is linked to propargyl via an ether moiety. The structure of fluorophore HF and probe HF-Pd are characterized by 1H NMR and mass spectra. The fluorescence spetra experiments proved that probe HF-Pd can react with palladium ions and further lead to the cleavage of propargyl, restoring the strong fluorescence of the fluorophore. The probe exhibits high selectivity and sensitivity toward palladium ions, with the detection limit being 0.83 μM. In addition, the probe can be applied to detect palladium ions in wide pH range, and is suitable for fluorescence bioimaging of palladium ions in living cells.