变温下荧光猝灭和加强理论公式合理性的比较  

Comparison of Reasonableness of the Fluorescence Quenching and Enhancement Equations at Different Temperatures

作　　者：杨曼曼[1] 席小莉[1] 杨频[1] 

机构地区：[1]山西大学化学化工学院分子科学研究所化学生物学与分子工程教育部重点实验室,太原030006

出　　处：《化学学报》2006年第14期1437-1445,共9页Acta Chimica Sinica

摘　　要：通过荧光和紫外方法研究盐酸左氧氟沙星、氟罗沙星、加替沙星和沃氟沙星四种喹诺酮类药物与人血清白蛋白(HSA)的作用,在不同温度下对荧光加强和猝灭理论公式的等价性和精细差异进行了比较,结果表明:在不同温度下两种理论公式尽管在求取解离常数上所得结果都可视为有效,但猝灭方程的双倒数图反而不及荧光加强方程的双倒数图与体现动态、静态猝灭机理的猝灭曲线一致.对于能量转移效率E,我们首次定义:按自由荧光体白蛋白的荧光强度F0和加入药物至荧光不再变化时的荧光强度F值计算F/F0,进而将F/F0代入0E1F=-F计算能量转移效率E.它标示出每个体系发生能量转移的最大限度,向体系中再添加药物,已不能发生进一步的猝灭,这一新定义的引入,使得能量转移效率E这一量值有可能推广到估算白蛋白运载药物能力的最大限度.Through the fluorescence and ultraviolet-visible spectrophotometry the action of HSA was studied with the four medicines of levofloxacin hydrochloride, fleroxacin, gatifoxacin and worfloxacin, and the reasonableness of the theories and equations of fluorescence enhancement and quenching at different temperatures was compared. The result shows： at different temperatures the outcomings obtained in determining dissociation constants with such two theories can be seen effective, but the doubly reciprocal curves of quenching equation are not conformed to quenching curves based on dynamic and static quenching mechanism as those of fluorescence enhancement. For the first time energy transfer efficiency E was defined as the fluorescence intensity ratio F/F0, where F0 is the fluorescence intensity of free HSA and F is the fluorescence intensity after addition of medicine till no change of its intensity. It shows the maximum limit when energy transfer occurs in every system, namely no more quenching takes place while addition of more medicine to the solution. The introduction of the new definition makes the energy transfer efficiency E extend to evaluate the limit of the ability of transferring medicine by the albumin possibly.

关 键 词：荧光猝灭和加强 能量转移效率 人血清白蛋白 喹诺酮类药物 

分 类 号：O657.3[理学—分析化学] S219.02[理学—化学]