Adsorption and release of phenolic compounds on ion exchange columns saturated with metal ions. (A preliminary study)

In order to evaluate the effects of interactions between phenolic compounds and metal ions fixed on cation exchange resins (SCX), standard solutions of phenolic compounds in ethanol were eluted through ion exchange columns for solid phase extraction (SPE) saturated with the ions Fe(III),Al(III), or Cu(II). The compounds which form complexes with these ions remained adsorbed on these columns, whereas the others were released. The subsequent elution with the mixture 1:1 ethanol/1N sulphuric acid then allowed the extraction also of adsorbed phenols. These results suggest the possibility of separating, by elution through ion exchange columns, classes of phenolic compounds of food products on the basis of their structural characteristics and of the cations present in ion exchange resins.