荧光光谱法研究硅钨酸及硅钨钴杂多酸与牛血清白蛋白的相互作用

Interaction between silicotungstic acid,silicon tungsten-cobalt heteropoly acid and bovine serum albumin by fluorescence spectrometry

摘要: 采用荧光光谱和紫外吸收光谱法研究了硅钨酸(SiW)及硅钨钴酸(SiWCo)与牛血清白蛋白(BSA)的相互作用，发现SiW和SiWCo与BSA的荧光猝灭为静态猝灭；其结合常数K_LB分别为4.94×10⁴、6.06×10⁴(298 K)与4.33×10⁴、5.86×10⁴(310 K)，结合位点数n均为1，它们与BSA相互作用方式为静电引力。采用同步荧光法考察了SiW和SiWCo对BSA构象的影响，发现SiW和SiWCo与BSA均发生了相互作用，但都没有改变BSA的构象，通过比较发现SiWCo与BSA作用活性比SiW强。

Abstract: The interactions of bovine serum albumin(BSA)with silicotungstic acid(SiW)and silicon tungsten-cobalt heteropoly acid (SiWCo) were studied by fluorescence and ultraviolet absorption spectroscopy.The fluorescence quenching of BSA with SiW and SiWCo was static quenching,and the binding constants at 298 K and 310 K were 4.94×10⁴,6.06×10⁴(298 K),4.33×10⁴,5.86×10⁴(310K),respectively.The number of binding site (n) was 1.The interaction of BSA with SiW and SiWCo was electrostatic force based on the thermodynamic parameters calculated at 298 K and 310 K.The conformation of BSA impacted by SiW and SiWCo was also discussed by synchronous fluorescence.The results showed that both SiW and SiWCo interacted with BSA,without changing its conformation,and the interaction between SiWCo and BSA was more active than that of SiW.