【摘要】 用荧光、同步荧光、三维荧光和紫外-可见吸收光谱法,研究了在生理条件下痢菌净(MEQ)与人血清白蛋白(HSA)相互作用的光谱学行为。分析了MEQ对HSA的荧光猝灭机制,计算了不同温度下的猝灭常数KSV、结合常数Kb、结合位点数n、热力学参数(如:ΔH、ΔS、ΔG)和结合距离r,并探研了MEQ对HSA构象的影响。结果表明:MEQ对HSA荧光猝灭方式是动态猝灭;结合位点数<1;结合距离<4.2 nm;MEQ对HSA构象的影响不大。MEQ与HSA间结合作用较弱,作为肠、胃或体外消炎药时,不易被血清白蛋白储存和转运,药物在体内的残留量较少、残留时间较短、所产生的副作用也较小。更多还原

【Abstract】 Fluorescence spectroscopy and UV-vis absorption spectroscopy were used to investigate the binding of antibiotic mequindox(MEQ) with human serum albumin(HSA) physiologically.The quenching mechanism of HSA with MEQ under fluorescence was discussed,results have indicated that it was a dynamic quenching process.Quenching constant KSV and thermodynamic parameters,such as ΔH,ΔG,ΔS etc.at different temperatures were calculated.The binding was mainly driven by entropy and hydrophobic forces played a major role in the process.Distance between HSA and MEQ was 4.2 nm calculated based on the theory of Frster′s no radioactive energy transfer.Furthermore,synchronous fluorescence spectroscopy and 3-dimensional fluorescence spectra were used to investigate molecular structure of HSA,with and without the existence of MEQ,results have indicated there was no structural change when considering experimental error.更多还原