铬(Ⅵ)-谷胱甘肽配合物诱导小牛胸腺DNA变性的新表征方法  

New Characterization Method on Denaturation of DNA Induced by Cr(VI)-GSH Complexes

作　　者：杨培慧[1,2] 张文豪[3] 赵秋香[3] 蔡继业[3] 

机构地区：[1]中国科学院安徽光学精密机械研究所 [2]暨南大学化学系,广州510632 [3]暨南大学化学系

出　　处：《无机化学学报》2006年第3期488-493,共6页Chinese Journal of Inorganic Chemistry

基　　金：广东省自然科学基金(No.021190);广州市科技计划项目(No.2003Z3-D2041)资助。

摘　　要：本文采用电化学方法对铬!-谷胱甘肽(GSH)配合物诱导DNA变性进行表征,同时运用原子力显微镜(AFM)对DNA损伤变性过程进行可视化探测。结果表明:在pH=5.6的HAc-NaAc缓冲溶液中,DNA溶液中加入Cr!-GSH配合物后进行循环伏安扫描,+0.20V和0.00V(vsSCE)处出现一对新的氧化还原峰,该氧化还原峰随Cr!-GSH配合物浓度增加峰电流上升。DNA热变性和表面活性剂SDS变性实验进一步证明了该峰为DNA变性后的氧化还原峰,且变性DNA的峰信号在修饰电极上比裸金电极上更为灵敏。电化学动力学表明在30min内配合物诱导DNA变性的程度随时间的上升而增加,并通过AFM观察了配合物作用下DNA断链的过程。The damages of DNA induced by Cr（VI）-GSH complexes were characterized by electrochemistry, absorption spectra, and AFM imaging. The redox peaks of denatured DNA appeared at potentials of about ＋0.20 V and 0.00 V in HAc-NaAc buffer solution （pH 5.6） when adding Cr（Ⅵ）-GSH complexes to the DNA solution. Moreover, the peaks current increased with the concentration of Cr（Ⅵ）-GSH complexes and incubation time. The results showed that the Cr（Ⅵ）-GSH complexes resulted in the denaturation of DNA. The heating and SDS denaturation further confirmed the DNA denaturation induced by the Cr（Ⅵ）-GSH complexes. AFM imaging was used to illustrate the cleavage process of DNA.

关 键 词：重铬酸钾 谷胱甘肽 电化学 DNA AFM 

分 类 号：O614.611[理学—无机化学] O629.72[理学—化学]