槲皮素-铜络合物的极谱法研究

Single-sweep Polarography of Cu (Ⅱ)-Quercetin

用单扫描极谱法研究了槲皮素（Ｑｕ）与Ｃｕ２＋形成络合物的条件及反应机理。在 ｐＨ ８．５０的磷酸盐缓冲溶液中，槲皮素与 Ｃｕ２＋络合并在－０．５９ Ｖ（ｖｓ．ＳＣＥ）处产生一个灵敏的还原峰，其峰高与 Ｃｕ２＋浓度在 ４．０ × １０－６～１．８ × １０－５ｍｏｌ／Ｌ范围内呈现良好的线性关系，检测限为 ３．０ × １０－６ｍｏｌ／Ｌ。测得络合物组成Ｃｕ２＋：Ｑｕ＝１：２，表观稳定常数为２．１０× １０１１。

The formative condition and mechanism of Cu (Ⅱ)-quercetin (Qu) complex have been studied. A reduction wave of Cu(Ⅱ)-Qu (complex) was obtained by single-sweep polarography at the medium of phosphate buffer (pH 8.50). The peak potential was at -0.59V( vs. SCE). The composition of the complex was determined as Cu (Ⅱ):Qu=1:2 and the condition formation constant was found to be 2. 10× 1011.