title: Nonaqueous capillary electrophoretic separation of polyphenolic compounds in wine using coated capillaries at high pH in methanol.
abstract: Nonaqueous capillary electrophoretic separation of a group of flavonoids (quercetin, myricetin, catechin, epicatechin) and resveratrol in wine was investigated in methanol at high pH. Malonate background electrolyte (pH* 13.5, ionic strength I = 14.2 mmol/L) provided highly repeatable separations of the analytes. Tests of untreated and coated (poly(glycidylmethacrylate-co-N-vinylpyrrolidone)) capillaries showed the analysis to be faster (6.5 min vs. 25 min) and the repeatability better in the coated capillaries. The coating procedure was simple and highly repeatable and the coating was stable during 40-45 runs. Determination of the last migrating peaks (epicatechin, resveratrol and catechin) was achieved merely by evaporating the wine samples and reconstituting the residue in methanol. For determination of the first migrating peaks (quercetin and myricetin) the samples were submitted to solid-phase extraction in C8 cartridges.
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, Helsinki, Finland.
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Demianová
authors.forename: Heli
authors.initials: H
authors.lastname: Sirén
authors.forename: Ruth
authors.initials: R
authors.lastname: Kuldvee
authors.forename: Marja-Liisa
authors.initials: ML
authors.lastname: Riekkola
mesh_terms: D055598:Chemical Phenomena; D002627:Chemistry, Physical; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D005419:Flavonoids / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D000432:Methanol / Q000737:chemistry; D000077185:Resveratrol; D013267:Stilbenes / Q000032:analysis*; D014920:Wine / Q000032:analysis*
chemical_list: D020099:Coated Materials, Biocompatible; D005419:Flavonoids; D013267:Stilbenes; D000077185:Resveratrol; D000432:Methanol