title: Determination of vitamin E in margarines and edible oils using square wave anodic stripping voltammetry with a glassy carbon paste electrode.
abstract: A new electroanalytical method for determination of vitamin E in the form of the total content of tocopherols present in margarines and edible oils has been developed. The method is based on extraction of these biologically active compounds into silicone oil, acting as lipophilic binder of glassy carbon paste electrode, with subsequent electrochemical detection by square wave anodic stripping voltammetry (SWASV) in 0.1M HNO3. The values of vitamin E contents were expressed as mass equivalent of α-tocopherol known as the most active form of this lipophilic vitamin. The linear ranges for α-tocopherol determination were 5×10-7-4×10-5and 5×10-8-1×10-5molL-1with the detection limits of 1×10-7and 3.3×10-9molL-1for 5 and 15min accumulation, respectively. The results have shown that SWASV with extraction step is very sensitive method for the determination of vitamin E, being comparable to reversed-phase high performance liquid chromatography chosen as reference method.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10, Czech Republic.
authors.forename: Milan
authors.initials: M
authors.lastname: Sýs
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10, Czech Republic.
authors.forename: Blanka
authors.initials: B
authors.lastname: Švecová
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10, Czech Republic.
authors.forename: Ivan
authors.initials: I
authors.lastname: Švancara
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10, Czech Republic. Electronic address: radovan.metelka@upce.cz.
authors.forename: Radovan
authors.initials: R
authors.lastname: Metelka
mesh_terms: D002244:Carbon / Q000737:chemistry*; D056148:Chromatography, Reverse-Phase; D004566:Electrodes; D008383:Margarine / Q000032:analysis*; D010938:Plant Oils / Q000737:chemistry*; D014810:Vitamin E / Q000032:analysis / Q000737:chemistry*
chemical_list: D010938:Plant Oils; D014810:Vitamin E; D002244:Carbon; D008383:Margarine
keywords: 1-Butyl-3-methylimidazolium hexafluorophosphate (PubChem CID: 2734174); Carbon paste electrode; Edible oils; Extraction; Margarines; Square wave voltammetry; Tocopherols; Vitamin E; alpha-Tocopherol (PubChem CID: 14985); alpha-Tocopheryl acetate (PubChem CID: 86472); delta-Tocopherol (PubChem CID: 92094); gamma-Tocopherol (PubChem CID: 92729)