烟酸和1,10-邻菲啰啉构建的Cu(Ⅱ)配合物与DNA的相互作用

The Interaction Between DNA and a Copper Complex Containing Mixed Ligands of Nicotinic Acid and 1,10-Phenanthroline

采用光谱法、循环伏安法和热变性方法,研究了烟酸(NA)和1,10-邻菲啰啉(Phen)构建的三元Cu(Ⅱ)配合物([Cu(Phen)(NA)]·H2O)与鲱鱼精DNA的相互作用。结果显示:NA中羧酸根离子与Phen中两个氮原子均与Cu(Ⅱ)双齿配位,形成的配合物在0.141~0.205V出现一对灵敏的氧化还原峰,并且配合物在玻碳电极上的反应主要由扩散过程控制。加入DNA后配合物的最大吸收峰发生了明显红移和减色,且配合物的氧化还原峰电流显著降低,式量电位发生正移;配合物能猝灭中性红(NR)-DNA体系的荧光,同时配合物的加入使DNA熔点升高,表明配合物与DNA存在嵌入结合。

A complex of[Cu（Phen）（NA）]·H_2O（Phen=1,10-phenanthroline,NA=nicotinic acid（NA）was synthesized,and the interaction between the complex and DNA was studied by spectroscopy,cyclic voltammetry（CV）and melting point determination.Results showed that-COO-in the NA and N in the Phen are liganded with Cu（Ⅱ）.CV curves showed that the complex have a pair of redox peaks at 0.141 V and 0.205 V,and the reaction of Cu（Ⅱ）on the electrode was diffusively controlled.With the addition of DNA,the UV absorption peaks of complex was red-shifted and the intensity is weakened,the complex can remarkably quench the emission intensity of NR-DNA system,and the peak current decreased significantly and potential moved positively.At the same time,the complex increased the melting point of DNA.All the above results demonstrated the intercalative interaction between the[Cu（Phen）（NA）]·H_2O with DNA.