两种铜配合物与DNA相互作用的紫外研究:pH和离子强度的影响

DNA Binding Properties of Two Copper(Ⅱ) Complex:Effect of pH and Ionic Strength

在不同溶液条件下,对两种铜配合物[Cu(atpy)(NO3)(H2O)](NO3).3H2O(1)和[Cu(ttpy)(NO3)2](2)(atpy=4′-p-9′-腺嘌呤基甲基苯基-2,2′:6,2″-三联吡啶,ttpy=4′-p-甲基苯基-2,2′:6,2″-三联吡啶)与小牛胸腺DNA(CT-DNA)的结合作用进行研究,紫外-可见光谱显示测试体系的pH以及离子强度均对两配合物与DNA的结合作用产生显著影响,其中在体系允许的测试范围内,pH越高,离子强度越低,两配合物与DNA结合作用越强。此外,配合物1与DNA相互作用受此影响更为明显,这可能与该配合物中含有的腺嘌呤基团有关。

The DNA binding properties of two copper（Ⅱ ） complexes, [-Cu（atpy）（NO3）（H20）] （NO3） · 3H2O （1） and [Cu（ttpy） （NO3）2 ] （2） （atpy = 4＇-p-9＇-adeninylmethylphenyl-2,2＇： 6,2″- terpyridine; ttpy = 4＇-p-tolyl-2, 2＇： 6, 2″-terpyridine）, with CT-DNA were studied by UV-vis spectroscopy in different buffer solutions. Results showed that pH values and ionic strength could influence the DNA binding strength and DNA binding modes of the two complexes. Higher pH value and lower ionic strength were proved to benefit the DNA binding properties. The buffer effect on the DNA binding property of complex 1 was more evident than that on complex 2 due to the introduction of the adeninyl group.