中文摘要：

以pH7.4、含有0．1mol·L^-1NaCl的0.01mol·L^-1 Hepes为缓冲液，在（25±0．2）℃，采用荧光光谱法研究了单宁酸（TA）与伴清蛋白（apoOTF）的相互作用．由蛋白内源荧光测定表明：TA分别与apoOTF,Tb^3＋N-apoOTF和Tb^3＋N-apoOTF-Tb^3＋c结合形成1：1配合物，其表观结合常数（KA）分别为7．15×10^5，4．16×10^6和3．77×10^6mol^-1·L．以Tb^3＋敏化荧光测定表明：TA与Tb^3＋可形成1：2配合物，且TA与Tb^3＋的结合能力大于apoOTF与Tb^3＋的结合能力．TA-Tb^3＋2配合物也可与该蛋白结合形成1：1复合物，其敝为1．86×10^5mol^-1·L．

英文摘要：

The interactions between tannic acid （TA） and apoovotransferrin （apoOTF） were studied by fluorescence spectroscopy with the spectroscopic probes of Tb^3＋ and intrinsic fluorescence of the protein in 0.01 mol·L^-1Hepes, at pH 7.4 and room temperature. The results showed that the complex with the molar ratio 1：1 was formed between TA and apoOTF, Tb^3＋N-apoOTF, Tb3＋N-apoOTF-Tb^3＋c, respectively. The binding constants of TA to apoOTF, Tb^3＋N-apoOTF and Tb^3＋N-apoOTF-Tb^3＋c was7.15×10^5,4.16×10^6and 3.77×10^6mol^-1·L , respectively. What＇s more, the tannic acid could bind to terbium ions, whose binding molar ratio was about 1 ： 2, and the binding ability of Tb^3＋ to apoOTF was weaker than that of Tb^3＋ to the tannic acid. Moreover, binding constant for attachment of TA-Tb^3＋ to apoOTF was 1.86×10^5 mol^-1·L, and the number of binding sites of the protein for TA-Tb^3＋2 was about 1.