中文摘要：

运用荧光光谱法研究pH对黄芩苷与牛血清白蛋白（BSA）相互作用的影响，结果表明：黄芩苷浓度的增加引起BSA在345am处荧光有规律地猝灭．荧光猝灭光谱及Stem—Volme方程分析发现，在pH为2．5、4．5和7．4体系中均为静态猝灭，且两者猝灭常数随pH增加而增加；Lineweaver—Burk双倒数方程计算pH7．4、温度为290K和310K下，黄芩苷和BSA的结合常数K分别为：K_（290）K=1．2894×10。L·mol^（-1）和K。。：1．0979×10。L·mol^（-2）由热力学参数确定黄芩苷与BSA之间的作用力类型为静电作用力．同步荧光光谱表明，黄芩苷使BSA芳香性氨基酸（Trp，Tyr）残基微环境的变化．

英文摘要：

The effects of pH on the interaction of the Baicalin with Bovine Serum Albumin（BSA） were studied by fluorescence quenching method. The fluorescence spectra showed that BSA fluorescence quench regulary with the addition of Baicalin at 345nm. The fluorescence quenching mechanims and Stem-Volmer equation Static quenching were also studied at pH 7.4,pH 4.5 and pH 2.5. The results showed that fluorescence quenching is staticand their quenching constant increased with increasing pH. The constants（K） of Baicalin binding with BSA are determined to be 1.289 4X 105 L· mol land 1.097 9X105· tool-- by the Lineweaver-Burk equation at pH 7.4 at the temperature of 290 K and 310 K. According to the thermodynamic parametersthe interaction between Baicalin and BSA is driven mainly by electrostatic force. Synchronous fluorescence spectra showed that the haicalin could change the microenvironment of BSA Tro and Tvr aromatic amino acid residues.