| It is an epoch of information science, synthetical chemistry and life science in 21th century, so the structure analysis, reform in structure and composition analysis of organic drugs developed hot studying fields at present. Electroanalytical chemistry is a useful tool for the study of organic drugs because of its obvious advantages in identification of effective compositions, metabolism kinetics of drugs, clinical mechanism of drugs and analysis of drug effect. In this thesis, organic drugs, especially isoflavonols that has the function of anticancer and eliminating 02" ' , are studied systematicly by many electroanalytical methods. These studies may provide theoretical and practical basis for biomedicine, and have important significance to broadening application range of electroanalytical chemistry.This thesis consists of five chapters, and main contents are as follows:1. Three kinds of new methods, oscillographic analysis of chemical reaction procedure of degradation and free radical reaction process, that of inclusion complex, coordinative system, are proposed. The degradation process of cephalexin in Imol/L NaOH solution and the elimination effect of isoflavonols to superoxide radical produced by the antoxidation of pyrogallol are investigated by oscillographic method. The experimental results show that the degradation process of cophalexin is a first order reaction, the reactive rate and half-life is 0.693mm"1 and 5.45mm"1, respectively. 3'-daidzein sulfonic sodium(DSS) and daidzein both have ability for scavege superoxide radical, and the former is more active. This is because the stability of reactive intermediates differ from each other. When the free radical attacks other materials, the main factor controlling the reactive rate is the stability of the intermediate. The bigger the conjugate extent is, the more stable the intermidiate is, and the faster the reactive rate is. There is a more stable reactive intermediate because of bigger conjugate extent and hydrogen bond between sulfonic radical and its neighbour hydroxide bond in DSS molecule. This study work indicates that oscillographic analysishas special advantages when it is used to monitoring some reactive procedure.A new oscillographic method based on inclusion reaction, which takes the analysis of Cu2+as an example, is founded. In 0.2 mol/L NaOH, p-CD can cause a pair of reversible incisions on dE/dt-E oscillogram. When Cu2+ is added to the solution of 0.2 mol/L NaOH contained p-CD, an inclusion complex between P-CD and Cu2+ is formed, and the incision depth on the cathodic branch on the oscillogram get shallow. This oscillographic charecteristic is applied to determination of Cu in silicon brass. Compared with other methods, this method has the advantages of cheap equipment and simple operation. Besides, it can conclude rapidly and intuitionisticly whether inclusion complex is formed between the host and guest.A new method of ocillographic analysis in coordination system is presented. The oscillographic charecteristic and mechanism of ARS and Ca-ARS in 0.1mol/L KOH or Zn-ARS in KBr are studied, and the coordination number and stability constant for Ca-ARS is 1:2 and 1.5 x109, respectively.2. The electrochemical behavior and reduction mechanism of daizein ramification such as DSS, 4',7-dimethoxy-3'-isoflavone sulfonic sodium(DISS), and 4'-hydroxy-7-methoxy-3'-isoflavone sulfonic sodium(HMISS) on mercury electrode are studied detailly, and the effect of these compounds on the eliminating of free superoxide radical are also explored by many electrochemical methods and spectroscopy techniques. In addition, the electrochemical behavior of atorvastatin calcium (AC) and its interaction between AC and p-CD are studied. The inclusion ratio and the forming constant of inclusion complex formed between P-CD and AC is 1:2 and 1.5 xlO9, respectively.Investigation on DSS, DISS and HMISS show that for DSS, three reductive waves can be observed in acidic solution from pH 1.0 to 6.2. In pH 1.0~3.2, there are two reduction waves of DSS...
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