采用具有天然抗肿瘤活性的药物苦参碱为配体,与Fe( Ⅲ)反应得到黄色的离子型苦参碱Fe( Ⅲ)化合物[ H-Matrine][ FeCl4],用X射线单晶衍射分析法确定了配合物的结构,并在模拟生理条件下,利用紫外光谱法、荧光光谱法、同步荧光光谱和圆二色谱法研究了化合物[ H-Matrine][ FeCl4]与人血清白蛋白( HSA)的相互作用。结果表明:[ H-Matrine][ FeCl4]对 HSA的荧光产生猝灭作用,猝灭机制为静态猝灭;[ H-Matrine][ FeCl4]与HSA在不同温度下的结合常数K和结合位点数n,及其相关热力学参数ΔH、ΔG、ΔS,室温时分别为:1.03×106L·mol-1、1.24、-68.63KJ·mol、-34.30KJ·mol和114.05J·mol,且其相互作用力主要是静电作用力。同步荧光光谱的结果表明:[ H-Matrine][ FeCl4]与HSA的结合位点靠近色氨酸,并使色氨酸的疏水性减弱。
Matrine,a natural antitumor active a herbal plant,was selected as a 1igand to react with Fe(Ⅲ)salt and to get a yellow [H-Matrine][FeCl4]ionic compound,which was characterized by single crystal X-ray diffraction analysis. The interactions of[H-Matrine][FeCl4]ionic compound with Human serum albumin(HSA)have investigated under the simulative human physiological conditions. The results of fluorescence spectrometry showed that the endogenous fluorescence of HSA has been significantly quenched by[ H-Matrine] [ FeCl4 ] and the mechanism of fluorescence quenching was static quenching. On the condition of room temperature(301K),the binding parameters and the thermodynamic parameters of[H-Matrine][FeCl4]and HSA are as follows:the binding constants is 1. 03×106L·mol-1,the numbers of binding sites is 1. 24,ΔH is-68. 63KJ·mol,ΔG is-34. 30KJ·mol andΔS is 114. 05J·mol,respectively. And the major driving force is Electrostatic interactions. The results of synchronous fluorescence demon-strated that the binding site of[ H-Matrine] [ FeCl4 ] and HSA is closer to tryptophan residues and the hydrophobicity of tryptophan residues was decrease.