Potentiometric determination of aqueous dissociation constants of flavonols sparingly soluble in water

被引：56

作者：

Herrero-Martinez, Jose M. ^{[1
]}

Repolles, Carme ^{[1
]}

Bosch, Elisabeth ^{[1
]}

Roses, Marti ^{[1
]}

Rafols, Clara ^{[1
]}

机构：

[1] Univ Barcelona, Dept Quim Analit, E-08028 Barcelona, Spain

来源：

TALANTA | 2008年 / 74卷 / 04期

关键词：

flavonols; dissociation constant; potentiometry; methanol/water mixtures;

D O I：

10.1016/j.talanta.2007.08.007

中图分类号：

O65 [分析化学];

学科分类号：

070302 [分析化学]; 081704 [应用化学];

摘要：

Two different approaches were evaluated and used to estimate the aqueous pK(a) values of some flavonols sparingly soluble in water (morin, fisetin and quercetin) from their pK(a) values in methanol/water mixtures obtained by potentiometry. Both approaches lead to similar results, although one of them requires only one pKa value at one unique methanol/water mixture, whereas the other (the classical Yasuda-Shedlovsky plot) requires several pKa data at different methanol/water mixtures. Thus, the first approach is recommended because it is faster and simpler. The automated potentiometric method is strongly recommended for pK(a) determination of these types of compounds because of its simplicity and speed of operation. (c) 2007 Elsevier B.V. All rights reserved.

引用

页码：1008 / 1013

页数：6

共 31 条

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