Studies On The Polarographic And Voltammetric Behavior Of Drugs And The Interaction Of Drugs With DNA

Based on the studying of the interaction of DNA with drugs, the pharmacological action of anticancer, antivirus have been explained at molecular lever and the novel method for DNA determining have been proposed. Since some drugs can accept electron when they are biologically reduced, then combine with DNA, the electrochemical action of these drugs were also primarily investigated. The two parts have been grouped into:1. The polarographic and voltammetric behavior of drugs: The polargraographic and voltammetric behavior of metronidazole and aristolochifc, A have been investigated by voltammetry, normal pulse polargraphy, osillopolarograph. In the base solution of B-R buffer solution containing KC1, a well-defined reduction peak of metronidazole and aristolochia A were obtained. The peak current directly proportioned to the concentration of metronidazole over the certain range, with sensitive detection limit and advanced correlation coefficient. The methods can be applied to the actual sample with satisfying result. The irreverisible adsorption characteristics of the peaks were proved by the experiments.2. The interaction of drugs with DNA: There are several interaction forms of drugs with DNA. However, the intercalation and hydrogen bonding are universal. Due to a new copper complex, the binding of the complex to fish sperm DNA was investigated by using fluorescence and absorption spectroscopy, continuous variation analysis, viscosity measurements, equilibrium binding and the salt dependence of the binding constant studies, fluorescence energy transfer experiments. The intercalation mode was proved to exist. Especially we found energy could transfer from bound ligand to DNA bases, which was provided additional evidence for the intercalation of copper complex into DNA and was used to explain the fluorescence spectroscopy.In addition, A novel fluorimetric method has been developed for rapid determination of DNA with palmatine hydrochloride (PMT) as a fluorescence probe, based on the fluorescence dramatical enhancement of PMT in the presence of DNA. The method is free from interference from a large number of foreign substances and is recommended for the determination of DNA in biological systems. All the reagents and reaction systems are stable and the procedure is easy to carry out. Moreover, Fluorescence, viscosity measurement, potassium ferrocyanide quenching studies have been used to characterize the interaction of PMT with fs DNA.