光谱和电化学方法研究黄芩素与核酸相互作用的机理

Spectroscopic and Electrochemical Methods on the Interaction Mechanism of Baicalein with DNA

在pH=3．22的NaAc—HAc溶液中，应用循环伏安法、方波伏安法、荧光光谱法、紫外可见光谱法和黏度法研究了黄芩素（BAI）与鲱鱼精子DNA（fsDNA）之间的相互作用，发现二者通过沟槽作用形成一电活性较高的复合物，fsDNA为BAI提供了一个低极性的疏水环境导致BAI的峰电流显著增强，增强的峰电流与fsDNA在7．0×10^-8～7．0×10^-6g／mL浓度范围内呈正比，由此建立了一种测定核酸的新方法，检测限达到4．1×10^-8g／mL。

Abstract The interaction between fish sperm DNA（fsDNA） and baicalein（BAI） in NaAc-HAc buffer（pH = 3.22） was investigated by using cyclic vohammetry, square wave vohammetry, fluorescence spectroscopy, ultraviolet visible spectroscopy and viscosity measurement. Their interaction is in a groove binding mode and the complex has a higher electrical activity. The peak current of BAI is enhanced significantly because fsDNA provides a low polar hydrophobie environment. The enhanced peak current is in proportional to the concentration of fsDNA in the range of 7.0 ×10-8～7.0×10-6 g/mL. Based on this observstion, a new method with a detection limits at 4. 1×10-8g/mL for the determination of nucleic acids is established.