α-球蛋白与稀土金属离子钆(Ⅲ)的配位作用

The Coordination Interaction of a-Globulin with Rare Earth Metal Ion Gadolinium ( Ⅲ )

采用固定顺磁金属离子浓度,逐渐改变α-球蛋白浓度,测定溶剂水质子弛豫时间变化的方法,研究了稀土离子钆(Ⅲ)与人血α-球蛋白的配位作用.研究结果表明,α-球蛋白中有3个钆(Ⅲ)离子的结合部位,其配合物的离解常数K_d=2.5×10^(-4)(mol/L)。

By using the method of fixing the concentration of paramagnetic metal ion and gradually changing the concentration of α-globulin, the proton relaxation time of solvent was determined, the complexation of a-globulin with gadoliniun ( Ⅲ ) was studied. The results show that there are three binding sites of Gd( Ⅲ ) in a-globulin molecule and the dissociation constant is 2. 5× 10-4 mol/L.