Study of the Photophysical Properties of Crown Porphyrin and Its Interaction between Amino Acid Drug
Because crown porphyrin contain both crown ether cycle and porphyrin large ring that all possess molecular recognition ability, this type of macro-molecule has attracted much attention of chemist all over the world. At present, Crown porphyrin has been widely used in the recognition of metal ions and organic micro-molecular and in the interaction between crown porphyrin and fullerene. Amino acid drug is a kind of most widely used biochemical drug, and more than a hundred kinds of amino acids and amino acid derivatives are used as therapeutic drug currently. Study of the interaction between bioactive molecular porphyrin and drug has great guiding effect on revealing the mechanisms of drug in human body. In this article, a symmetrical crown porphyrin and its metal complex were synthesized. Their photophysical properties were systematically studied, and crown porphyrin was successfully used as a spectral probe in the determination of amino acid drug.Firstly, the structure, synthesis, application status and development trend are discussed in the introduction of the article. Then the research status and significance of porphyrin aggregates and amino acid drug are presented. The main contents of the study are provided as follows:1. The synthesis and characterization of symmetrical crown porphyrin and its metal complex. Classical Alder synthesis method was used in the synthesis of symmetrical H2-5,10,15,20-Tetra-(benzo-crown-5)-porphyrin and its zinc metal complex 5,10,15,20-Tetra(benzo-crown-5)-porphyrinatozinc(II). Purification was conducted using neutral alumina column. And products were characterized using infrared spectrum, nuclear magnetic resonance, ultraviolet-visible absorption spectrum and fluorescence spectrum. The experiment results showed that we have obtained the desired production.2. Photophysical properties of H2-5,10,15,20-Tetra-(benzo-crown-5)-porphyrin was firstly studied using ultraviolet-visible absorption spectrum, fluorescence spectrum and resonance light scattering. The spectral properties of the crown porphyrin in different kinds of organic solvent, in different proportions of ethanol/water solutions, in different acidity conditions and in various surfactants solutions were researched. The complete data provided reference for the application of crown porphyrin in spectral analysis.3. The aggregation behavior of H2-5,10,15,20-Tetra-(benzo-crown-5)-porphyrin in chloroform solvent and anionic surfactant was studied. Characterization means of absorption spectrum, fluorescence spectrum and resonance light scattering were used and the results indicated that the crown porphyrin can form regular J-aggregates both in chloroform solvent and in anionic surfactant sodium dodecylbenzene sulfonate (LAS). In the study of its aggregation behavior in LAS solution, the influences of acidity and ionic strength were discussed, and the formation mechanism of porphyrin-surfactant J-aggregates was preliminary investigated.4. Rayleigh scattering method was used to study the interaction between H2-5,10,15,20-Tetra-(benzo-crown-5)-porphyrin and amino acid drug L-glutamine, and a new method was established for the determination of L-glutamine. The determiantion conditions were investigated, such as the selection of acidity and the dosage of buffer solution, effect of the concentration of porphyrin, the selection of reaction medium and its dosage, effect of different addition orders of the reagents, effect of organic micromolecule and ionic strength and influence of reaction time and coexisting substances. Under the optimum experimental conditions, the working curve of the system was established. The method established in the paper has low detection limit and good selectivity and a satisfactory result was obtained when the method used in the determination of L-glutamine in commercial drug.