土贝母皂苷II与人血清白蛋白相互作用机制的光谱研究
刘璐莎;樊君;胡春梅;孙洋;胡晓云;赵英永;魏嵩;梁旭华
【期刊名称】《化学学报》 【年(卷),期】2011(069)021
【摘要】The presence of binding sites of human serum albumin makes it possible to combine many drugs target.The efficacy of tubeimosideII（TBMSII）,isolated from Bolbostemma paniculatum（Maxim）,binding to human serum albumin（HSA） is critical for pharmacokinetic behavior of TBMSII.The interactions between TBMSII and HSA under simulative physiological conditions were investigated by the methods of fluorescence spectroscopy.Fluorescence data revealed that the fluorescence quenching of HSA by TBMSII was the result of the formation of the TBMSⅡ-HSA complex.According to the modified Stern-Volmer equation,the binding constants（Ka） between TBMSⅡ and HSA at four different temperatures（293,298,303,308 K） were 1.002×10^5,0.701×10^5,0.514×10^5,0.411×10^5
Lomol-1
respectively.The thermodynamic parameters,enthalpy change（ΔH） and entropy change（ΔS） for the reaction were calculated to be -44.829 kJomol-1 and-57.497 Jomol-1oK-1 according to van＇t Hoff equation,indicating that the hydrogen bonds and hydrophobic interactions play a dominant role in the binding of TBMSII to HSA.Site marker competitive experiments indicated that the binding of TBMSⅡ
土贝母皂苷II与人血清白蛋白相互作用机制的光谱研究
