Preparation And Fluorescence Properties Of Chitosan And Tyrosine-Containing Polypeptide Fluorescence Complex

In recent years,fluorescence technology has been widely concerned with the development of science and technology.Fluorescence analysis technology can be applied in biology and chemistry.The fluorescent material is easy to observe and the fluorescent probe has high sensitivity and selectivity.Therefore,the fluorescent probes with excellent performance designed by researchers are widely used in the identification and detection of specific ions.However,how to realize the integration of fluorescent probes and design new fluorescein derivatives suitable for biological detection on the existing basis are the key issues to be further studied.In this paper,chitosan and tyrosine-containing peptides were used as basic materials to investigate the performance of the designed fluorescent probe and the synthesized oxidized fluorescent complex,which provided ideas for the development of fluorescence technology.Chitosan nanoparticles were prepared by oxidation degradation and ionic crosslinking.Chitosan-quercetin drug-loaded microspheres were labeled with fluorescein isothiocyanate,and their drug loading rate,encapsulation efficiency and antioxidant properties were investigated.Their inhibitory effects on Escherichia coli and Staphylococcus aureus were also tested.The drug-loaded microspheres prepared in this experiment had a certain inhibitory effect on Escherichia coli and Staphylococcus aureus.In this experiment,the antibacterial performance was visually analyzed.The fluorescent probe was prepared by crosslinking chitosan with rhodamine B.And iron ions could quench the fluorescent probe.The quenching effect of different iron salts on the fluorescent probe was explored,and the detection range was 10^-5～10^-2mol/L.The preparation method was simple and easy to operate,and the results were intuitive and easy to observe,which provided ideas for detecting iron ions in water.Using tyrosine-containing polypeptide as reaction substrate,dityrosine and and its polymer with characteristic blue fluorescence were obtained by enzyme catalysis and characterized by UV-vis absorption spectrum,fluorescence spectrum and mass spectrum.Under the experimental conditions,when the concentration of hydrogen peroxide was different,the polymer types of the reaction products were different.This experiment provided ideas for monitoring the H₂O₂concentration in the system.