Synthesis And Application Of Ruthenium Complex-based Probes For The Detection Of Reactive Sulfur Species

Compared with traditional organic fluorescent molecular probes,ruthenium complex fluorescent probes have many advantages such as good luminescent properties and chemical stability,excitation and emission in the light region,larger Stoks shift,and longer luminescent lifetime.And by modifying the structure of its ligands,its luminescence properties can be well regulated.In this thesis,by introducing different recognition sites to the ligands of the probe molecules,a fluorescent molecular probe for detecting HSO 3-in an actual sample and a fluorescence probe for selectively distinguishing and recognizing GSH were designed and synthesized,respectively.In the first part of this work,a fluorescent molecular probe Ru-azo for selective detection of HSO3-was firstly designed,synthesized characterized,and it was applied for the phosphorescence detection and time-gated luminescence detection o f HSO3-in food samples.The ruthenium complex was introduced a 1,10-phenanthroline ligand modified an azo group as a recognition group and 2,4-dinitrobenzene as a quenching group.Under the PET mechanism,Ru-azo itself has very weak fluorescence due to the presence of 2,4-dinitrobenzene with strong electron-withdrawing properties in the probe molecule.When the probe specifically binds to HSO3-,due to the affinity addition reaction,new adducts including-HSO3 are generated,and the original PET process is changed,so the probe molecule generates strong fluorescence signal.The probe doesn't interfere by biological thiols,and can specifically recognize HSO3-under neutral conditions,and the maximum fluorescence signal intensity can increase by about 8 times.Taking the advantage of the long luminescence lifetime of ruthenium complexes,combined with the time-gated luminescence detection method,quantitative analysis of HSO3-in complex food samples containing short-lived fluorescent background interference can be achieved,and the accuracy of the method is verified by recovery experiments.Subsequently,based on the research progress of GSH probes and the excellent performance of ruthenium complex molecular probes,a fluorescent probe for selective detection of GSH was designed and preliminarily synthesized.This probe was modified one of the 2,2-bipyridine ligands,introduced a naphthalimide derivative.A sulfonamide group as a specific recognition site was linked between 2,2-bipyridine ligand and naphthalimide to form a ruthenium complex probe for the detection of GSH.