邻菲啰啉和氨三乙酸钴配合物与牛血清白蛋白相互作用的荧光分析

Abstract

利用溶液法合成了邻菲啰啉(PHEn)和氨三乙酸(H3nTA)钴配合物CO(PHEn)2Cl2(1),nA[CO(nTA)].H2O(2),[CO(PHEn)2(H2O)2][CO(nTA)(PHEn)]2.12H2O(3),对配合物3进行了X射线单晶衍射表征,结果表明:该配合物属三斜晶系,P1空间群,A=1.2448(2)nM,b=1.5898(3)nM,C=1.7412(3)nM,α=91.746(3)°,β=97.807(3)°,γ=103.745(3)°,V=3.309(1)nM3.利用荧光光谱法研究了室温下这3种配合物与牛血清白蛋白(bSA)的相互作用,并测定了不同温度下这3种配合物与bSA相互作用的荧光强度变化,确定配合物1和3对bSA的荧光猝灭方式均为静态猝灭;分析了配合物1和3与bSA相互作用时的结合常数、结合位点数以及热力学函数与温度之间的关系,进一步讨论了这2种配合物分别与bSA相互作用时的作用位点、作用力的类型以及两者之间的距离.

Cobalt complexes [Co(phen)2Cl2(1),Na[Co(nta)]·H2O(2),[Co(phen)2(H2O)2]·[Co(nta)(phen)]2·12H2O(3)](phen: phenanthroline,nta: nitrilotriacetate) were synthesized in solution,and the structure of complex 3 was characterized by single-crystal X-ray diffraction analysis(XRD).It crystallized in the triclinic system,space group P1 with a=1.2448(2) nm,b=1.5898(3) nm,c=1.7412(3) nm,α=91.746(3)°,β=97.807(3)°,γ=103.745(3)°,V=3.309(1) nm3.The interaction between bovine serum albumin(BSA) and complexes 1—3 was investigated with fluorescence spectra at room temperature.Fluorescence quenchings were shown as static quenching for complexes 1 and 3 based on the fluorescence spectrum at different temperatures.The binding constant,binding sites and thermodynamic functions were calculated.The interaction sites,binding force and distance for BSA with complexes 1 and 3 were discussed respectively.