title: Determination of procyanidins and their metabolites in plasma samples by improved liquid chromatography-tandem mass spectrometry.
abstract: An off-line solid-phase extraction (SPE) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for determining procyanidins, catechin, epicatechin, dimer, and trimer in plasma samples. In the validation procedure of the analytical method, linearity, precision, accuracy, detection limits (LODs), quantification limits (LOQs), and the matrix effect were studied. Recoveries of the procyanidins were higher than 84%, except for the trimer, which was 65%. The LODs and LOQs were lower than 0.003 and 0.01 microM, respectively, for all the procyanidins studied, except for the trimers, which were 0.8 and 0.98 microM, respectively. This methodology was then applied for the analysis of rat plasma obtained 2h after ingestion of grape seed phenolic extract. Monomers (catechin and epicatechin), dimer and trimer in their native form were detected and quantified in plasma samples, and their concentration ranged from 0.85 to 8.55 microM. Moreover, several metabolites, such as catechin and epicatechin glucuronide, catechin and epicatechin methyl glucuronide, and catechin and epicatechin methyl-sulphate were identified. These conjugated forms were quantified, in reference to the respective unconjugated form, showing concentrations between 0.06 and 23.90 microM.
authors.affiliation: Department of Food Technology, Escola Tècnica Superior d'Enginyeria Agrària, Universitat de Lleida, Lleida, Spain.
authors.forename: Aida
authors.initials: A
authors.lastname: Serra
authors.forename: Alba
authors.initials: A
authors.lastname: Macià
authors.forename: Maria-Paz
authors.initials: MP
authors.lastname: Romero
authors.forename: Maria-Josepa
authors.initials: MJ
authors.lastname: Salvadó
authors.forename: Mario
authors.initials: M
authors.lastname: Bustos
authors.forename: Juan
authors.initials: J
authors.lastname: Fernández-Larrea
authors.forename: Maria-José
authors.initials: MJ
authors.lastname: Motilva
mesh_terms: D000818:Animals; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D008297:Male; D010636:Phenols / Q000097:blood; D044945:Proanthocyanidins / Q000097:blood*; D051381:Rats; D017208:Rats, Wistar; D012015:Reference Standards; D015203:Reproducibility of Results; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry; D027843:Vitis / Q000737:chemistry*
chemical_list: D007202:Indicators and Reagents; D010636:Phenols; D044945:Proanthocyanidins