中文摘要：

在pH 7.4的Tris-HCl缓冲液中,通过荧光光谱、紫外-可见光谱、圆二色谱（CD）以及粘度实验和熔点实验研究农药氰戊菊酯与小牛胸腺DNA的相互作用。实验结果发现,随着氰戊菊酯浓度增大,DNA农药体系出现紫外增色,CD谱收缩现象,DNA的粘度和熔点明显增大,说明氰戊菊酯主要以嵌入方式与DNA结合,氰戊菊酯可导致DNA链增长,破坏右手螺旋以及碱基堆叠。测定不同温度（293,302,310K）下氰戊菊酯与DNA之间的表观结合常数,并通过Van’t Hoff方程计算出两者作用的热力学参数焓变（ΔH）和熵变（ΔS）分别为78.63kJ.mol-1和359.5J.mol-1.K-1,据此推测疏水作用是两者结合的主要驱动力。

英文摘要：

The interaction between fenvalerate and calf thymus DNA at pH 7.4 in Tris-HCl buffer was in- vestigated by fluorescence, UV-vis absorption, and circular dichroism （CD） spectroscopy, as well as viscosity measurements and DNA melting techniques. It was found that fenvalerate molecules could intercalate into the base pairs of DNA,evidenced by hyperchromicity in UV-vis absorption with the increasing concentration of the fenvalerate,and the decrease in iodide quenching effect,CD spectral constringency,and the significant increase in the relative viscosity and denaturation temperature of DNA. The intercalation binding of fenvalerate to DNA resulted in the damage of base stacking and the decrease of right-handedness of DNA. Moreover,the association constants were obtained from the fluorescence quenching data at three dif- ferent temperatures. The thermodynamic parameters enthalpy change （AH） and the entropy change （AS） were calculated to be 78.63 kJ.mol^-1 and 359.5 J. mo1^-1.K^-1 respectively from the Van＇t Hoff equation,which suggested that hydrophobic interaction was the main driving force in the binding of fenvalerate to DNA.