Electrochemical Studies Of Interaction Of Antibiotics And DNA

With the development of modern techniques of chemical synthesis, compound separation, chemical molecular structure analysis, and the theory and investigation techniques of molecular recognition, much attention are paid to the interaction of DNA with other molecules recently. DNA modified electrode has some advantages over the conventional method, such as less sample consumption, higher sensitivity and signal/noise ratio and so has made great progress in the field concerning DNA studies, especially construction of biosensor and gene chips. Molecular self-assembled monolayers(SAMs) modified have been widely investigated during the last two decades. However, SAMs modified electrodes have seldom been used as the substrate for adding antibiotics on it and form a novel multi-layer film.Based on the above view, the electrochemical studies of interaction between DNA and antibiotics, the electrochemical property and their application of the DNA modified monolayers and kanamycin SAM/Au by self-assembling have been probed.Chapter I IntroductionA brief review on the electrochemical study progress of interaction between DNA and target molecule, DNA modified electrode and the development about chemically modified electrodes including the theory, study methods and application in the area of analytical chemistry is presented.Chapter II Electrochemical Investigation on Interaction between Oxytetracyclin and DNAThe DNA modified glassy carbon electrode prepared using "air-drying/adsorption" method was characterized by means of cyclic voltammetry (CV) and it proved to be good stability. The electrochemical behaviors of oxytetracyclin are probed by CV and differential-pulse voltammetry (DPV). The interaction of oxytetracyclin with calf thymusDNA is also studied. And the interactive mode between oxytetracyclin and DNA is verified by the fluorescence method. The results of sample determined by electrochemical method are consistent with those done by UV spectrophotometry.Chapter HI Electrochemical and Microscopic Studies of Surface-Confined DNAWe have studied the micropatterning and characterization of the organic monolayers using cyclic voltammetry (CV), scanning electrochemical microscope (SECM), atom force microscope (AFM), and A.C. impedance and determined the electrochemical parameters, i.e., apparent reaction rate constant (&/), and the coverage of electrode surface (6). Using the high sensitivity of the electron transfer of ferricyanide to the modification of the gold surface with DNA, we selected this reaction as a probe to study the different modification stages at this modified electrode. SECM images obtained from bare and partially and totally modified electrodes showed very good resolution with different topography or null according to the extent of modification. Based on a comparison with the results from experiments, it can be obtained a reasonable agreement, which means a conjunction of these techniques.The DNA monolayer exhibited good stability and long lifetime. It can stand solution washing, hence is suitable for electrochemical studies. The voltammetric behavior of electro-active compounds, kanamycin and erythromycin at the DNA-modified gold electrode was explored. According to the electrochemical parameters, it can be concluded that both kanamycin and erythromycin interact with DNA through intercalation.Chapter IV Electrochemical Studies of Kanamycin Immobilization on Self-Assembled Monolayer and Interaction with DNAA novel self-assembled monolayer (SAM) modified gold electrode (SAM/Au) was prepared by layer-by-layer self-assembly method. The resulting electrode was characterized by cyclic voltammetry and electrochemical impedance spectroscopy usingK3Fe(CN)6 as a probe. In could be proved the formation of kanamycin SAM/Au. Furthermore, the electrochemical characteristics of kanamycin onto self-assembled monolayer (SAM) modified gold electrode (SAM/Au) are investigated by cyclic voltammetry..In the potential range 0-0.6 V, Cu(II) yields a pair of stable re...