几种金属离子对胭脂红与牛血清白蛋白相互作用的影响——荧光光谱研究

利用荧光光谱法研究了不同温度(15、27、39℃)下食用合成色素胭脂红对牛血清白蛋白(BSA)的内源荧光猝灭特性,考察了Cu2+、Ni 2+、Pb2+等金属离子对二者相互作用的影响,并测定了不同温度下的猝灭常数KSV、结合常数KA和结合位点数n.结果表明,3种金属离子基本不影响胭脂红对BSA荧光猝灭机理,但Cu2+、Ni 2+、Pb2+离子都与BSA有一定的结合能力,可在不同程度上增强胭脂红与BSA的结合作用及其对BSA内源荧光的猝灭.

Effects of several metal ions on the interactions between Ponceau 4R and bovine serum albumin---fluorescence spectroscopic study

Fluorescence spectroscopic method was adopted to study the quenching characteris-tics of endogenous fluorescence of bovine serum albumin （BSA ） by synthetic food pigment Ponceau 4R at different temperatures （15 ,27 and 39 ℃） ,and the effects of metal ions Cu2＋ , Ni2＋ and Pb2＋ on the interactions between BSA and Ponceau 4R were investigated .Moreover , the quenching constant KSV ,binding constant KA ,and binding site n under different tempera-tures were measured .Results indicate that the three kinds of metal ion almost have no effect on the fluorescence quenching mechanism of BSA by Ponceau 4R .However ,Cu2＋ ,Ni2＋ and Pb2＋are in some way able to combine with BSA ,thereby enhancing the interactions between BSA and Ponceau 4R as well as the quenching of the endogenous fluorescence of BSA .