A Study On The Chemiluminescent Behavior Of Some Flavonoids And Alkaloids

With the progress of the society and the improvement of the human living standard, the requirement for natural medicine is increasing quickly in the world. Therefore, it is very significant to study the characteristics of the effective compositions of traditional Chinese medicine and it is very important to develop the determination method for these effective compositions. Due to its high sensitivity, simplicity and relatively low cost, chemiluminescence (CL) analysis has its special advantage in the drugs analysis. Several methods for research on the CL behavior of some flavonoids and alkaloids have been developed in this thesis. The thesis consists of four chapters. In Chapter one, an overview of the properties of flavonoids and alkaloids, the principle and characteristics of CL analytical method, and applications of CL method for analysis of flavonoids and alkaloids were involved. Moreover, the principle and application of sonochemiluminescence (SCL) and photochemiluminescence (PCL) were also involved in this chaper. At the end of this chapter, the aims of this thesis and the main research contents were described. In Chapter two, the CL properties of the flavonoids in the system of sodium hypochlorite-ethanol have been studied and a new CL analytical method for determination of the flavonoids has been eatablished. The optimum conditions for the CL emission were investigated. It was founded that the CL behaviour of thirteen flavonoids was greatly enhanced in the present of ethanol. The linear relationship between the CL intensity and the flavonoids concentration was established respectively under the optimum condition. Based on the detail investigation of the CL spectrum, the fluorometric spectrum and ultraviolet absorbed spectrum of fisetin in the system of sodium hypochlorite-ethanol, the possible mechanisms of the CL reaction was discussed. In Chapter three, the CL properties of synephrine and sinomenine in the system of potassium permanganate-H~+ have been studied and a new CL analytical method for determination of synephrine and sinomenine has been eatablished. Under the best condition, synephrine in the concentration range of 4.00×10-7～2.00×10-5 mol/L can be determined with a detection limit of 7.0×10-8 mol/L and sinomenine in the concentration range of 3.60×10-8～4.80×10-6mol/L can be determined with a detection limit of 4.0 ×10-9 mol/L. The method has been successfully applied to the determination of synephrine in tropicamide, phenylephrine eye drops and the determination of sinomenine in sinomenine HCl tablet. In Chapter four, the PCL properties of lucigenin in DMF and the inhibitory effect of flavonoids on this PCL system have been studied. The factors that influenced the intensity of PCL were investigated and the possible mechanisms of PCL was discussed. By comparing the inhibitory ability of 16 flavonoids on PCL, the relationships between structure and 1O2-scavenging activity of the flavonoids were discussed. In Chapter five, the SCL properties of lucigenin in DMF and the flavonoids inhibitory effect on SCL have been studied. The factors that influenced the intensity of SCL were investigated and the possible mechanisms of SCL was discussed. By comparing the inhibitory ability of 16 flavonoids on PCL, the relationships between structure and ROO·-scavenging activity of the flavonoids were discussed.