【作者】 曲松；

【导师】 冶保献；

【作者基本信息】 郑州大学 ， 分析化学， 2004， 硕士

【摘要】 众所周知，抗癌药物在对癌症的治疗中日益重要。鉴于其固有的毒副作用，有必要建立一些灵敏度高选择性好的分析方法来对其进行检测。另外，DNA是许多抗癌药物作用的首要靶分子。因此，研究DNA和抗癌药物的相互作用不仅有助于了解抗癌药物的作用机理，而且对于人工合成DNA靶向抗癌药物分子的设计也很有意义。本论文研究了抗癌药物甲氨蝶呤和秋水仙碱的电化学行为以及6—巯基嘌呤与DNA的相互作用。其主要内容如下： 1．研究了甲氨蝶呤（MTX）在悬汞电极上的电化学行为。在pH为9.20的Britton-robinson（B-R）缓冲溶液中，MTX在悬汞电极上有一对很明显的受吸附控制的氧化还原峰。示差脉冲伏安法（DPV）测得MTX还原峰峰电流与MTX浓度在5.0×10^-8mol／L～1.0×10^-5mol／L范围内有良好的线性关系。检测下限为5.0×10^-9mol／L。将该测定：方法用于注射用甲氨蝶呤中MTX含量的定量分析，结果令人满意。同时还详细地研究了MTX在悬汞电极上的电极反应过程，推测了电极反应机理。结果表明，MTX的还原属于具有吸附性的准可逆过程，并伴随2个电子、2个氢离子参与电极反应。 2．研究了抗癌药物秋水仙碱（COLC）在玻碳电极上的电化学行为。在HAc-NaAc缓冲溶液中，循环伏安扫描发现，COLC在玻碳电极上产生一不可逆的氧化峰，峰电位为1.22V（vs SCE）。用差示脉冲伏安法测定，峰电流与COLC浓度在8.0×10^-7mol／L～1.0×10^-5mol／L范围内有良好的线性关系，检测下限达1.0×10^-7mol／L。将之应用于血清样品的测定，结果令人满意。同时，对电极反应机理进行了初步探讨，秋水仙碱在玻碳电极上是一个两电子，两质子的不可逆氧化过程。 3．用电化学方法研究了抗癌药物6-巯基嘌呤（6-MP）与DNA的相互作用。随着作用时间的增加和DNA浓度的增加，6-MP的氧化峰和还原峰峰电位都发生了正移，同时峰电流逐渐降低。实验考察了6-MP与单链，双链DNA作用强弱的不同。结果表明：DNA与6-MP形成了非电活性的化合物，其结合比是1：1，结合常数是5.17×10⁶。同时对DNA与6-MP电极过程机理进行了研究，并求取了电化学参数。最后，依据加入DNA后还原峰电流的降低还可以定量测定DNA。更多还原

【Abstract】 It is well known that anticancer drugs have become increasingly important in the treatment of tumor.In view of their inherent risk of toxicity,the development of highly sensitive and selective analytical methods for measuring anticancer drugs is therefore necessary. Moreover Deoxyribonucleic acid (DNA) is the primary target molecule for most of anticancer dnig.So the study of interaction between anticancer drug and DNA is helpful not only to understand the action mechanisms of some antitumor drugs.but also to the design of artificial DNA-targeting drug molecule. In this paper, the electrochemical behavior of the anticancer drugs Methotrexate(MTX) and Colchicine(COLC) have been studied. The interaction between 6-Mercaptopurine (6-MP) and DNA have been studied too. The main results are expressed as below:1. The electrochemical characteristics of methotrexate are studied by using different electrochemical methods at the mercury drop electrode. In Britton-Robinson buffer solution (pH9.20), a pair of redox peaks of methotrexate controlled by adsorption is obtained by cyclic voltammetry. The differential pulse voltammetry peak current is proportional to the concentration of methotrexate in the range of 1.0 10-5 mol/L~ 5.0 10-8mol/L with the detection limit of 5.0 X 10-9mol/L, which has been used in real sample analysis with satisfactory result. Moreover, the electrode reaction mechanism of the system are studied and the kinetic parameters are obtained too.The electrode reduction of MTX is a quasi-reversible process with two electrons and two protons.2. The electrochemical behavior of colchicine is studied at the glassy carbon electrode. In 0.2mol/L HAc-NaAc buffer (pH4.60), an oxidative peak of COLC is obtained by cyclic voltammetry. The peak potential is at 1.22V(vs.SCE). The anodic peak current obtained by differential pulse voltammetry is proportional to the concentration of COLC in the range of 8.0 10’7mol/L~ 1.0 10-5mol/L with the detection limit of 1.0 10-7mol/L.The proposed method has been applied to the determination of COLC in human serum with satisfactory result. Moreover, the electrodereaction mechanism of the system are studied and some kinetic parameters are obtained too.3. The electrochemical studies of interaction between 6-mercaptopurine and DNA are performed in 0.2mol/L HAc-NaAc buffer (pH5.6). Both reduction and oxidation peak currents decrease and the peak potentials also shift positively with the increasing of time and DNA concentration respectively. The result shows the reaction of DNA with 6-MP have formed an electrochemically non-active complex. The composition of the complex is 1:1. The combining constant is 5.17 106 .Simultaneously, the electrode reaction process have been investigated by electrochemical techniques, and its dynamic parameters have been obtained too.The decrease in peak current is proportional to DNA concentration and can be used to determine DNA concentration.更多还原