Selective adsorption of flavonoids on cerium-doped ferroferric oxide magnetic particles

Ce-doped Fe3O4 magnetic particles (Ce-Fe3O4 MPs) were synthesized by co-precipitation method. The coordination and adsorption properties of Ce-Fe3O4 MPs to different natural products were investigated. The results verified that the "catechol-like","maltol-like" and "acetylacetone-like" donor sets of flavonoids were the binding sites with Ce-Fe3O4 MPs. The adsorption was conformed to be pseudo-second-order model and single-layer adsorption after being characterized by adsorption kinetics and adsorption thermodynamics. The adsorption and desorption conditions were optimized. It was found that different components adsorbed on the Ce-Fe3O4 MPs surface can be selective desorbed in different solvents, which was helpful for the selective separation to adsorbed components. The Ce-Fe3O4 MPs were successfully applied to selective adsorption of compounds containing "catechol-like", "maltol-like" and "acetylacetone-like" donorsets in the crude extract of Scutellaria baicalensis Georgi and Rheum palmatum L. The results demonstrated that the magnetic solid phase extraction (MSPE) method based on Ce-Fe3O4 MPs has the advantages of high structural selectivity, high efficiency and low consumption, and can be used for efficient separation of flavonoids with specific structures from natural products. (C) 2021 Published by Elsevier B.V.