头孢地嗪钠与牛血清白蛋白相互作用研究

用荧光光谱法研究水溶液中头孢地嗪钠(CDZM)与牛血清白蛋白(BSA)的结合反应, 测定了头孢地嗪钠与牛血清白蛋白的结合常数和结合位点数, 探讨了其荧光猝灭机制. 根据热力学参数确定了头孢地嗪钠与牛血清白蛋白之间的作用力类型, 运用Föster偶极-偶极非辐射能量转移原理, 测定了头孢地嗪钠与牛血清白蛋白相互结合时其授体-受体间的距离, 采用同步荧光技术考察了头孢地嗪钠对牛血清白蛋白构象的影响.

Study on the Interaction between Cefodizime Sodium and Bovine Serum Albumin

The binding reaction between cefodizime sodium (CDZM) and bovine serum albumin (BSA) in aqueous solution was studied by fluorescence spectra. The binding constant KA was found to be 5.31×104 and the binding sits n to be 0.94 at 299 K by fluorescence quenching method. The quenching mechanism of fluorescence of BSA by cefodizime sodium has been discussed. The thermodynamic parameters of binding reaction were determined as follows： the molar change of enthalpy ΔrHm=－15.8 kJ•mol-1, the molar change of Gibbs function ΔrGm=－27.0 kJ•mol-1 and the molar change of entropy ΔrSm=－90.0 J•K-1•mol-1, and the binding power between cefodizime sodium and bovine serum albumin has been considered. Furthermore, the binding distance (r=3.13 nm) between cefodizime sodium and bovine serum albumin was obtained according to the theory of Föster′s dipile-dipile non-radiation energy transfer mechanism, and the effect of cefodizime sodium on the conformation of bovine serum albumin was analyzed using synchronous fluorescence spectrometry.