Cu^(2+)、Pb^(2+)和Ni^(2+)对日落黄与牛血清白蛋白作用的影响研究

Spectroscopic studies on characteristics of the interactions between sunset yellowand bovine serum albumin in the presence of Cu(Ⅱ),Ni(Ⅱ) and Pb(Ⅱ)

利用荧光光谱法,在Cu2+、Pb2+和Ni2+存在时,不同温度下食用合成色素日落黄(FCF)对牛血清白蛋白(BSA)的内源荧光猝灭的特性进行了研究。测定了三个温度下的猝灭常数K SV,结合常数K A,结合位点数n。经过比较发现,有无金属离子,FCF对BSA荧光猝灭机理基本一致。Cu2+和Ni2+离子虽然也有与BSA结合的倾向,但总的趋势是加强了FCF与BSA的相互作用。Pb2+则不同,不同程度地减弱了FCF与BSA的结合作用,可能与Pb2+结合蛋白质能力更强有关。

Under different temperatures ,the interaction between sunset yellow and bovine serum albumin（BSA） are studied by fluorescence spectra in the presence of Cu（II） ,Pb（II） ,and Ni（II）. The quench constants Ksv（L/mol） ,binding constants KA（L/mol） and Number of binding sites n are measured either. After comparison,FCF is basically the same with BSA fluorescence quenching mechanism whether there is Metal ion or not. Though the existence of Cu （II） and Ni （II） reflected the tendency to combine with BSA,it eventually strengthen the interaction between sunset yellow and bovine serum albumin （BSA）. But the existence of Pb2＋ weakened the effect of combination of sunset yellow and bovine serum albumin（BSA） to varying degrees ,which may relate to Stronger binding force between Pb2＋ and Protein.