水溶性金属席夫碱与DNA相互作用的荧光光谱

研究了几种水溶性的金属席夫碱与 DNA相互作用的光谱性质。在所研究的金属中 Mn的络合物与 DNA的相互作用最强，荧光强度改变最大且其激发和发射峰均有微小紫移。其紫外可见光谱亦有明显的减色效应和微紫移。 KI猝灭和 Mn席夫碱与溴化 3， 8 _ 二氨基 _ 5 _ 乙基 _ 6 _ 苯基菲啶的竞争实验证实了 Mn席夫碱与 DNA之间的作用方式是嵌入方式。同时也考察了 pH值、温度对 Mn席夫碱及 Mn席夫碱－ DNA体系荧光强度影响。 Mn席夫碱仅与 DNA的一部分键位发生作用， Mn席夫碱相对荧光强度与加入的小牛胸腺 DNA的浓度，在 3× 10－ 6～ 2× 10－ 4 mol/L范围内呈线性关系。水溶性 Mn席夫碱可以作为一种新型荧光探针用于微量 DNA的检测。

Fluorescence Analysis of Water _ soluble Metal Complexes of Schiff -base with DNA

The fluorescence spectral characteristics and interaction of Mn-, Ni-, Cu-metal complexes of N,N′ -di -(5 -triethyl amminomethyl -salicyclidene) -ethylenediamine with DNA are described. Among the complexes tested, Mn-Schiff -base bound to DNA shows the most decrease fluorescence intensity with a little blue shift of excitation and emission peaks. KI quenching and competitive binding between Mn-Schiff -base and ethidium bromide for DNA were studied. The results showed that the interactive model Mn-Schiff -base and DNA was an intercalative one. The effect of pH and temperature on fluorescence were also investigated. A linear relationship between F/F0 and concentration of calf thymus DNA covers a range of 3× 10-6～ 2× 10-4 mol/L. Mn-Schiff -base can be used for determining trace of calf thymus DNA as a new fluorescence probe.