The Electrochemical Study On The Flavones And The Interaction Of Flavones With Biological Molecules

The research discoveries that flavones compounds have many potential pharmaceutical and biologic activations, such as their anti-virus and anti-tumor anti- inflammation effects. Deoxyribonucleic acid (also named DNA) is the important chemical substance transfering base of information in the course of our life. A number of biochemical and molecular biological investigations have revealed that DNA is frequently the targets for therapeutically active small molecular. More scientists pay attention to the study of the interaction of small molecular and the DNA including the interaction mechanism and pattern, which are benefit to explain the essence of medicinal effect moleculars, design the new factional medicine having functions for surmounting many difficult diseases such as cancer and virus and develop biology information science.Based on the important meaning of interaction medicinal effect moleculars with DNA this paper is mainly to study electrochemistry behavior of two different structural flavones Lutelin and Kaempferol and the interactions of their with DNA under given condition by means of elctrochemistry and UV-Vis spectroscopy. The relationship between the structure characteristics of these two compounds and interaction pattern or mode of the flavonoids with DNA was preliminarily discussed. The knowledge may make us better understand the mechanics and pattern of action and pharmacological activities of them and open up new way to design the most suitable flavonoid derivatives with structural changes. At the same time three methods of voltammetric determination of DNA and Cytochrome C using Luteolin and Kaempferol as electrochemical probe were established carving out the new means.The main contents of this thesis are expressed as follows:1. In 0.04 mol/L B-R(pH=4.00) buffer solution electrochemistry behavior of Lu has been studied by some electrochemical methods. Lu took place into the redox interaction that was a quasi-reversible process controlled by adsorption with two electrons and two protons. And other electrochemical kinetics parameters such as charge coefficientα=0.90, standard electon transfer rate constant k_s=2.96 s^-1 and the maximum surface coverageΓ_T of 6.20×10^-10 mol/cm² had been obtained and the possible interaction mechanism was discussed. What's more, the result indicated: a good linearity between the oxidation peak currents and the concentration of Lu in range of 8.00×10^-8 mol/L～8.00×10^-6 mol/L with the detected limit of 7.14×10^-8 mol/L. The method is simple operation and high accuracy with the detect recovery between 98.54% and 104.0%, which may be applied in detecting Lu.2. The interaction of Lu with DNA has been studied depending on Lu's electrochemistry characters. In the B-R(pH=4.00) buffer solution the intercalation of Lu and DNA took place by forming an electrochemical inactive supramolecular complex DNA-Lu resulting in the peak current decreased and the peak potential shifted positively. The electrochemical kinetics parameters such asαand k_s in the absent and present of DNA were estimated, which also showed the form of the DNA-Lu as the same as Ultraviolet-visible spectra of Lu and DNA. And the combine number m of the interaction of 2 and the combine constantβof 3.02×10¹¹ were also calculated. In addition, the oxidation peak currents were a good linear relationship with the concentration of DNA in range of 2μg/mL～12μg/mL, and the linear regression equation was i_pa(μA×10)=8.68-0.322[DNA] (μg/mL) with correlation coefficient 0.989. So, a voltammetric determination method of DNA was founded. And the result of the method was satisfactory.3. In 0.04 mol/L B-R(pH=4.91) buffer solution Lu can interact with Cyt-C by electrostatic binding caucing the peak current decreased while the peak potential shifted positively. In addition, the oxidation peak currents were a linear relationship with the concentration of Cyt-C in range of 1μg/mL～16μg/mL, and the linear regression equation was i_pa(μA×10)=15.0-0.269[Cyt-C] (μg/mL) with correlation coefficient 0.999. And the result of the method was satisfactory.4. In 0.04 mol/L B-R(pH=2.91) buffer solution the electrochemistry behavior of Ka has been studied. Ka took place into the incomplete redox interaction that was a incomplete reversible process controlled by adsorption with two electrons and two protons. The electrochemical kinetics parameters such asα=0.55, k_s=6.18 s^-1 which make better discuss the possible interaction mechanism andΓ_T of 1.02×10^-9 mol/cm² had been obtained.5. The interaction of Ka with DNA has been studied on the basis of Lu's electrochemistry characters. In the B-R(pH=2.90) buffer solution the intercalation of Ka and DNA took place by forming an electrochemical inactive supramolecular complex DNA-Ka leading to the peak current decreased and the peak potential shifted positively. The electrochemical kinetics parameters such asαand k_s in the absent and present of DNA were estimated, which also showed the form of the DNA-Ka as the same as Ultraviolet-visible spectra of Lu and DNA. And the combine number m of the interaction of 2 and the combine constantβof 4.28×10⁹ were also calculated. In addition, the oxidation peak currents were a good linear relationship with the concentration of DNA in range of 2μg/mL～16μg/mL and the linear regression equation was i_pa(μA×10)=0.4-0.389 [DNA](μg/mL) with correlation coefficient 0.989. So, a voltammetric determination method of DNA was founded. And the result of the method was satisfactory and receivable.