title: Microchip electrophoresis with amperometric detection for a novel determination of phenolic compounds in olive oil.
abstract: The relevance of the development of microchip electrophoresis applications in the field of food analysis is considered in this work. A novel method to determine important phenolic compounds in extra virgin olive oil samples using a miniaturized chemical analysis system is presented in this paper. Three interesting phenolic compounds in olive oil and fruit (tyrosol, hydroxytyrosol and oleuropein glucoside) were studied by end-channel amperometric detection using a 100 μm gold wire as working electrode in glass microchip electrophoresis. The electrochemical behavior of these compounds was studied and the medium to carry out their detection was selected (0.1 M aqueous sulfuric acid). The best conditions for the separation were achieved in sodium tetraborate (10% methanol, pH 9.50) with different concentrations for the sample and the running buffer in order to allow the sample stacking phenomenon. The injection was carried out using 600 V for 3 s and the separation voltage was set at 1000 V. The quality of the method was evaluated through its analytical figures of merit and by its performance on real extra virgin olive oil samples. Determination of these compounds was carried out using the standard addition calibration method with good recoveries.
authors.affiliation: Departamento de Química Analítica, Universidad de Extremadura, Spain. pgodoy@unex.es
authors.forename: María del Pilar
authors.initials: Mdel P
authors.lastname: Godoy-Caballero
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Acedo-Valenzuela
authors.forename: Teresa
authors.initials: T
authors.lastname: Galeano-Díaz
authors.forename: Agustín
authors.initials: A
authors.lastname: Costa-García
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Fernández-Abedul
mesh_terms: D002138:Calibration; D004563:Electrochemistry / Q000379:methods*; D046209:Electrophoresis, Microchip / Q000379:methods*; D005898:Glass / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D000069463:Olive Oil; D010636:Phenols / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D010938:Plant Oils / Q000737:chemistry*
chemical_list: D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; D006046:Gold