荧光探针技术研究阿特拉津与ct-DNA的相互作用

Study on the Interaction of Atrazine and ct-DNA by Fluorescence Probe Technique

利用分子荧光探针和紫外吸收光谱技术研究了阿特拉津(Atrazine)与小牛胸腺DNA(ct-DNA)之间的相互作用。实验中选用溴化乙锭(EB)为荧光探针,考察了阿特拉津浓度、磷酸盐、离子强度以及碘化钾对系统荧光的影响。结果表明,阿特拉津对ct-DNA-EB体系的荧光存在猝灭现象,并同时存在静态和动态两种猝灭方式。KI对ct-DNA-Atrazine体系的荧光猝灭及阿特拉津使ct-DNA紫外吸收的增色和红移现象表明阿特拉津与ct-DNA之间存在嵌插作用。磷酸盐、离子强度对ct-DNA-EB-Atrazine体系的荧光强度影响表明,阿特拉津与ct-DNA的磷酸基之间存在非特征性的静电作用,并且高离子强度不利于这种作用。

The interaction atrazine and ct-DNA was studied using fluorescence probe and UV absorption spectroscopy technique. Ethidium bromide （EB） was used as a probe. The effects of atrazine, phosphate, concentration of ions, and potassium iodide on the fluorescence of ct-DNA-EB system were investigated. The results showed that the fluorescence quenching process of atrazine to ct-DNA-EB system was proved to be the simultaneous dynamic and static quenching model. The phenomena of fluorescence quenching of ct-DNA-atrazine system by KI and hyperchromicity and the red shift of DNA UV-absorption caused by atrazine indicated the existence of intercalation between atrazine and ct-DNA. The experiments of phosphate and ionic strength showed that atrazine could combine with the phosphate group of ct-DNA by non-characteristic static force, and this action could be inhibited by high ionic strength.