Flavonoids as Analytical Reagents

Compounds from the flavonoid family, while exhibiting a wide range of biological effects, are interesting reagents for analytical purposes as well. They form complexes with several p-, d-, and f-electron metals, which could be employed in the determination of these metal ions in different kinds of samples by various techniques. This article presents and discusses the application of flavonoid compounds as chromogenic agents in spectrophotometric and fluorometric detection, as complexing modifiers in solid phase extraction for preconcentration and separation of metal ions, and in adsorptive voltammetry for the determination of metals. Selected applications are included to illustrate the scope and limitations of the various approaches.