4种金属卟啉配合物与血清白蛋白作用的光谱研究

Spectroscopy on the interaction between four metalloporphyrin complexes and serum albumin

应用荧光光谱法研究了4种金属卟啉配合物5-(4-羧基苯基)-10,15,20-三苯基卟啉锌、钴、镍、锰(MCPPZn、MCPP-Co、MCPPNi、MCPPMnCl)与牛血清白蛋白(BSA)的结合反应。探讨了金属卟啉配合物对BSA内源荧光的猝灭机理,根据不同温度下的结合常数判断金属卟啉配合物与BSA之间具有较强的结合作用,对BSA内源荧光的猝灭过程为静态猝灭。根据热力学参数确定了MCPPZn与BSA之间的作用力以静电引力为主,MCPPCo(25和42℃下)、MCPPNi、MCP-PMnCl与BSA之间的作用力以氢键和范德华力为主。分析了结合常数和作用力类型的差异主要是由中心金属离子的电负性和外层d轨道上的电子数的不同而引起的。

The mechanism interaction between four metalloporphyrin complexes including 5-（4-carboxyphenyl）-10,15,20-triphenylporphyrin zinc,cobalt,nickel,manganese（MCPPZn,MCPPCo,MCPPNi,MCPPMnCl） and bovine serum albumin（BSA） was studied by means of fluorescent spectroscopy.The rnechanism of fluorescence quenching of BSA caused by four metalloporphyrin complexes was investigated.The binding constants were measured at different temperatures,which showed that the combinations between these four metalloporphyrin complexes and BSA were large,and the sort of quenching on BSA was a static quenching procedure.According to the thermodynamic parameters,the main sorts of binding force could be confirmed as electrostatic force between MCPPZn and BSA,hydrogen bond and van der Waals force between MCPPCo（25 or 42 ℃）,MCPPNi,MCPPMnCl and BSA.The differences of binding constants and the sorts of quenching force were produced mainly by electro-negativity and electron number on outer d-orbit of central metal ion.