【摘要】 采用紫外光谱和荧光光谱研究了配离子 [Cu(A) 2 ]2 +(其中A =邻菲络啉 ( phen) ,联吡啶 (bpy) ,乙二胺 (en) )与小牛胸腺DNA的相互作用。实验发现配合物的存在使DNA碱变性的 pH增大 ,变性后增色效应减小。EB DNA体系的荧光强度随 [Cu( phen) 2 ]2 +的加入迅速减弱。在DNA存在下 ,配离子被猝灭剂 [Fe(CN) 6]4-的发光猝灭程度减小。进一步研究了配体分子平面的大小对配合物与DNA作用的影响。结果表明 ,铜配合物与DNA之间发生了插入作用 ,且该作用随配体芳环平面的减小而减弱 ,即 [Cu( phen) 2 ]2 +>[Cu(bpy) 2 ]2 +>[Cu(en) 2 ]2 +。更多还原

【Abstract】 The interaction of 2+ (A=phen,bpy,en) complex ion and ct DNA was investigated by using absorption spectra and fluorescence spectra. Based on the measurement of A 260 in the different pH mediums, the alkaline denaturation curves of DNA in the absence and in the presence of [Cu(phen) 2] 2+ complex ion were obtained. The result showed that the alkaline denaturation for [Cu(phen) 2] 2+ complex ion occured at a higher pH than that for DNA alone. The absorption of EB DNA system in the presence of [Cu(phen) 2] 2+ showed that [Cu(phen) 2] 2+ could partly sustain the place of EB. The result of fluorescence spectra suggested that the [Cu(phen) 2] 2+ complex ion could make the fluorescence intensity of EB DNA system to decreased sharply. The effect of 4- on the emission of [Cu(phen) 2] 2+ and [Cu(phen) 2] 2+ DNA system was studied. All the experimental results indicated that the intercalative binding mode was the major mode for the interaction of [Cu(phen) 2] 2+ complex ion and DNA, and the size of ligands can effect the binding of complexes to DNA.更多还原