光谱法研究铬(Ⅵ)与血红蛋白的相互作用  

Interaction between Chromium(Ⅵ) and Hemoglobin:Spectroscopic Approach

作　　者：张根成[1] 范苏[1] 

机构地区：[1]盐城师范学院应用化学与环境工程研究所,盐城224002

出　　处：《无机化学学报》2009年第7期1199-1204,共6页Chinese Journal of Inorganic Chemistry

基　　金：江苏盐城师范学院教授基金资助项目(No.06YSYJB0205)

摘　　要：运用荧光光谱、紫外光谱、CD光谱法研究了K2Cr2O7与牛血红蛋白(BHb)的相互作用。紫外光谱表明,加入铬(Ⅵ)酸根离子后,BHb分子中Soret带的吸收持续降低,峰位红移,说明铬(Ⅵ)酸根离子可能使部分血红素辅基从BHb的空腔中脱离出来,部分转变为高铁血红蛋白。荧光光谱表明,铬(Ⅵ)酸根离子与BHb形成基态复合物导致BHb内源荧光猝灭,猝灭机理主要为静态猝灭。测定了不同温度下该反应的热力学参数,表明上述作用过程是一个熵增加、自由能降低的自发分子间作用过程,铬(Ⅵ)酸根离子与BHb之间以氢键和范徳华力相互作用为主;并用同步荧光和CD光谱技术考察了铬(Ⅵ)对BHb结构的影响。The interaction between chromium （Ⅵ） and bovine hemoglobin （BHb） was investigated using fluorescence, UV-Vis and CD spectroscopy. The experimental results showed that the Soret band was decreased gradually with the increased amount of Cr（Ⅵ）, suggesting the detachment of some heme chromophores from their matrixes in BHb and the formation of MetHb; the fluorescence quenching of BHb by chromium（Ⅵ） is a result of the formation of Cr（Ⅵ）-BHb complex; static quenching was confirmed to result in the fluorescence quenching. The corresponding thermodynamic parameters were measured at different temperatures. The process of binding Cr（Ⅵ） on BHb was a spontaneous molecular interaction procedure in which entropy increased and Gibbs free energy decreased. The hydrogen bonds and Van der Waals forces interactions play a major role in stabilizing the complex. The effect of Cr（Ⅵ） on the conformation of BHb was analyzed using synchronous fluorescence and CD spectroscopy.

关 键 词：铬(Ⅵ) 牛血红蛋白 荧光光谱 热力学参数 

分 类 号：O614.613[理学—无机化学] O613.72[理学—化学]