摘要
用荧光光谱及紫外光谱法模拟研究生理条件下胡椒酸与牛血清白蛋白(BSA)的相互作用。结果表明,胡椒酸与BSA形成基态复合物从而猝灭BSA的内源性荧光,猝灭原因主要为静态猝灭和非辐射能量转移。胡椒酸对BSA的猝灭速率常数Kq为2.969×1013(18℃)、2.491×1013(25℃)和2.328×1013L·mol-1·s-1(37℃)。胡椒酸与BSA的结合常数KA为1.01×105(18℃)、2.06×104(25℃)和1.02×104L·mol-1(37℃),结合位点数n为0.90(18℃)、0.77(25℃)和0.72(37℃)。根据Frster偶极-偶极非辐射能量转移理论得到结合距离r为2.47(18℃)、2.52(25℃)和2.54(37℃)nm。确定胡椒酸与BSA有较强的相互作用,可以被蛋白质所储存和运输。
The interaction between piperic acid and bovine serum albumin(BSA) under physiological conditions was investigated using fluorescence spectroscopy(FS) and absorption spectroscopy.The experimental results showed that the piperic acid molecules inserted into the hydrophobic pockets of BSA and quenched the intrinsic fluorescence of BSA by forming piperic acid-BSA complex.The mechanism of fluorescence quenching was confirmed combining by both static quenching and nonradiative energy transferring.The quenching constants(Kq) are 2.969×1013(18 ℃) and 2.491×1013(25 ℃)、 2.328×1013 L·mol-1·s-1(37 ℃).The apparent binding constants(KA) between piperic acid and BSA are 1.01×105(18 ℃)、 2.06×104(25 ℃)、 1.02×104L · mol-1(37 ℃),and the value of binding sites(n) are 0.90(18 ℃) and 0.77(25 ℃) and 0.72(37 ℃).According to the Frster theory of non-radiation energy transfer,the binding distances(r) were 2.47(18 ℃)、 2.52(25 ℃)、 2.54 nm(37 ℃).Which indicate that the interaction of piperic acid and BSA was driven mainly by Van der Waals force.
出处
《分析试验室》
CAS
CSCD
北大核心
2013年第1期5-8,共4页
Chinese Journal of Analysis Laboratory
基金
国家自然科学基金(81060366)
内蒙古自然科学基金(2010BS1203)资助
关键词
胡椒酸
牛血清白蛋白
荧光光谱
相互作用
Piperic acid
Bovine serum albumin
Fluorescence spectroscopy
Interaction