乳酸-钴(Ⅱ)-1,10-菲啰啉三元配合物与DNA结合的光谱与电化学研究

以1,10-菲啰啉(phen)和乳酸为配体合成了三元钴配合物Co(phen)(la)_2]。采用紫外光谱、循环伏安法、计时库仑法和微分脉冲伏安法等考察了其与鲱鱼精天然DNA的相互作用。紫外光谱实验显示,在Co(phen)(la)_2]中加入DNA后,配合物在270 nm处的紫外特征吸收峰出现明显的减色效应,并伴随红移,表明Co(phen)(la)_2]可通过其phen配体插入DNA中相邻碱基对。循环伏安法和计时库仑法进一步表明,与DNA结合后,复合物在水溶液中扩散系数降低,从而导致电化学信号减弱。微分脉冲伏安实验显示,Co(phen)(la)_2]氧化峰电流与DNA浓度在2.66×10~(-5)~1.34×10~(-4)mol/L范围内呈现良好的线性关系,表明Co(phen)(la)_2]可作为一种潜在的DNA检测探针。

Spectroscopic and Electrochemical Investigation on the DNA-binding Property of a Cobalt(Ⅱ) Complex with Mixed-ligands of Lactic Acid and 1,10-Phenathroline

A ternary cobalt complex Co(phen) (la)2] has been synthesized by the reaction of cobalt salt with 1,10-phenanthroline (phen) and lactic acid.The interaction of the complex with natural fishsperm DNA was investigated by UV absorbance spectroscopy,cyclic voltammetry,chronocoulometry and differential pulse voltammetry.The results of UV absorbance spectroscopy at 270 nm revealed that DNA could induce the hypochromic effect and red-shift of characteristic absorbance peak of the complex,suggesting that the cobalt complex can interact with DNA via a typical intercalation binding mode.The cyclic voltammetry and chronocoulometry further showed that the diffusion coefficient of the complex was decreased after the interaction of the complex with DNA.Quantitative analysis by differential pulse voltammetry demonstrated that the cobalt complex can be successfully used for the detection of DNA as an electrochemical probe,with a linear response range of 2.66 × 10-5 ～ 1.34 × 10-4 mol/L.