摘要
在模拟生理条件下,采用分子荧光、紫外光谱法研究了水溶液中Cd2+与牛血清蛋白(BSA)的相互作用.研究表明,在pH=7.0缓冲液中,以280nm作为激发波长,342nm作为发射波长,Cd2+对BSA的荧光发射有较强猝灭作用.实验测定了Cd2+与BSA在289K,306K和319K温度下的结合常数Ka分别为5.31×104,5.22×104,4.70×104,其热力学参数ΔHm=-3.07kJ·mol-1;ΔSm=79.83J·mol-1·K-1.结果表明导致BSA荧光猝灭是由于分子内的非辐射能量转移而引起的静态猝灭,他们之间的主要作用力是静电作用力.
Under the simulative physiological conditions,the interaction between cadmium ions and bovine serum albumin were studied in aqueous solution by molecular fluorescence and ultraviolet spectrometry methods.The results showed that the best quenching effects of cadmium to BSA occurred in buffer solution at pH=7.0and the optimum excitation and emission wavelength are 280nm and 342nm,respectively.Binding constant of cadmium ions and bovine serum albumin at 289K,306Kand319Kare 5.31×10^4,5.22×10^4 and 4.70×10^4,respectively.The thermodynamic parameters calculated from Gibbs-Helmholtz equation in this study areΔHm =-3.07kJ· mol-1,ΔSm=79.83J·mol-1·K-1,respectively.Fluorescence data revealed that the quenching mechanism of BSA by cadmium ions were static quenching processes resulting from the nonradiation energy transfer within the molecule and electrostatic effect between the protein and the cadmium is the main bindingforce.
出处
《分子科学学报》
CAS
CSCD
北大核心
2014年第3期240-245,共6页
Journal of Molecular Science
基金
青岛市科技计划基础研究项目(13-1-4-226-jch)
青岛农业大学高层次人才科研基金资助项目(631104)
