二维铅(Ⅱ)配位聚合物的合成、结构表征及其与BSA作用

Synthesis,Structural Characterization and BSA Interactions of Two-Dimensional Lead(Ⅱ)Coordination Polymer

以吡啶-2,6-二甲酸和硝酸铅为原料,在室温下合成了[(C7H3NO4Pb)n]配位聚合物。单晶结构测试表明,该晶体属于单斜晶系,P21/n空间群,晶胞参数a=9.7395(4)A,b=5.5386(2)A,c=14.1755(6)A,α=90°,β=104.501(4)°,γ=90°,V=740.31(5)A^(3),Z=4。用荧光光谱和紫外可见光谱研究了配位聚合物与牛血清白蛋白(BSA)的相互作用,结果表明,配位聚合物对BSA有荧光猝灭作用,属于静态猝灭。分别计算了298 K、308 K温度下配合物与BSA间的结合常数(Ka)、结合位点(n)及相关热力学参数(ΔH<0,ΔS<0,ΔG<0),表明二者间主要以氢键和范德华力键合,且随温度升高,配合物与BSA间的作用减弱。根据Forster非辐射能量转移理论,求得BSA与配位聚合物间的距离r=3.52 nm,说明配位聚合物与BSA分子间发生了非辐射能量转移。

The coordination polymer[(C7H3NO4Pb)n]was synthesized bypridine-2,6-dicarboxylic acid and Pb(Ⅱ)at room temperature.And its structure was confirmed by X-ray single crystal diffraction.The crystal belongs to monoclinic system,P21/n space group,unit cell parameters a=9.7395(4)A,B=5.5386(2)A,C=14.1755(6)A,α=90°,β=104.501(4)°,γ=90°,V=740.31(5)A^(3),Z=4.The interaction between complex and bovine serum albumin(BSA)was studied by fluorescence spectroscopy and UV-vis spectroscopy.The results showed that complex had fluorescence quenching effect on BSA,and the quenching mechanism was static quenching.The binding constant(Ka),binding site(n)and related thermodynamic parameters(ΔH<0,ΔS<0,ΔG<0)between the complex and BSA at 298 K and 308 K were calculated.It showed that the complex and BSA were mainly combined by intermolecular hydrogen bond and Vander Waals force.And the interaction between the complex and BSA decreased with the increase of temperature.According to Forster′s non-radiative energy transfer theory,the distance between BSA and the complex was 3.52 nm(r=3.52 nm),indicated that the non-radiative energy transfer occurred between the complex and BSA molecules.