槲皮素伏安行为及其稀土络合物极谱催化氢波研究

Studies on the Polarographic Behaviors of Quercetin and the Catalytic Hydrogen Waves of Heavy Rare Earth Ions-quercetin System

在乙醇量小于5％的水溶液中，于pH1．5至4．5，4．2至9．5分别得到槲皮素的两个还原波，均为羰基两电子还原．前者为其分子的强吸附波，后者为一价阴离子的波．在pH6．1附近的醋酸盐缓冲底液中，可获得槲皮素与Tb（Ⅲ）、Dy（Ⅲ）、Ho（Ⅲ）、Er（Ⅲ）、Tm（Ⅲ）、Yb（Ⅲ）、Lu（Ⅲ）和Y（Ⅲ）等重稀土离子络合物的双重表面催化氢波．络合物被诱导吸附，组成为（REL2）L吸．Sc（Ⅲ）与槲皮素形成单一表面催化氢波，其组成为（ScL）L吸．

The electrochendcal behavior of quercetin among the pH range from 1.5 to 9.5 was studied. In the pH 1.5 to 4.5 and 4.2 to 9.5, two reducing waves were obtained respectively. The former is an irreversible adsorptive wave of molecular quercetin and the latter is an irreversible wave of anodic ion of quercetin. In the buffer sohition of 0.1mol·L(-1) HAc-NaAc, at pH 6.1, the surface catalytic hydrogen waves of the complexes of heavy rare earth ions-quercetin were obtained by single-sweep polarography. The compositions of adsorptive complexes were determined as RE(Ⅲ): Qu=1:3 by using polarography. In the solution, the compositions of the complexes were determined as RE(Ⅲ): Qu=1:2 by using photometry. This means that the adsorption of the complex is the pattern of induced adsorption.