甲硝唑与牛血清白蛋白相互作用的热力学特征研究

Study on Thermodynamics Features of Interaction of Metronidazole with Bovine Serum Albumin

在模拟人体生理条件下,用荧光猝灭光谱、同步荧光光谱和紫外可见吸收光谱等,研究了25℃、31℃和38℃下甲硝唑(MET)与牛血清白蛋白(BSA)相互作用的热力学特征。采用Stern-Vol mer方程、Lineweaver-Burk双倒数方程和热力学方程等分析实验数据,得到了相互作用常数KLB的平均值为3.116×104L.mol-1,热力学参数ΔHθ、ΔGθ和ΔSθ的平均值分别为-1.259 kJ.mol-1、-25.73 kJ.mol-1和80.47 J.K-1,结合位点数的平均值为1.086;实验表明,MET与BSA可结合形成具有一定结构的复合物,其荧光猝灭作用更符合静态猝灭作用特征,主要作用力可能是静电力。为研究MET的治病机制、生物学效应和生态环境效应等提供了重要信息。

Under the imitated physiological condition of human body and different temperatures,the interaction of metronidazole（MET） with bovine serum albumin（BSA） was studied by means of fluorescence quenching spectrum,synchronous fluorescence spectrum and ultraviolet-visible absorption spectrum.After analyzing and disposing the fluorescence quenching data by Stern-Volmer equation,Lineweaver-Burk equation and thermodynamic equation,the average value of bonding constant（KLB：3.116×104L·mol-1）,thermodynamic parameters（ΔHθ：-1.259 kJ·mol-1,ΔGθ：-25.73 kJ·mol-1,ΔSθ：80.47 J·K-1） and number of bonding site（1.086） were obtained.It had been proved that BSA could react with metronidazole and form a new compound in this system.The quenching belonged to static fluorescence quenching and the action force for each other was static interaction.It provided important information for studying therapeutic mechanism of MET,and its biological effects and environmental effects,etc.