title: Analysis of unsaponifiable compounds of edible oils by automated on-line coupling reversed-phase liquid chromatography-gas chromatography using the through oven transfer adsorption desorption interface.
abstract: An automated method for analysis of unsaponifiable compounds in edible oils is presented. The method involves the on-line coupling of reversed-phase liquid chromatography and gas chromatography (LC-GC) using the through oven transfer adsorption desorption (TOTAD) interface. The oil is injected directly with no sample pretreatment step other than filtration. It may also be considered to dilute the oil sample. In the LC step, a short C4 column using a methanol/water eluent separates analytes from the other components of the oils, which are made up of mainly triglycerides. A LC fraction of up to 1.6 mL containing the analytes is transferred to GC at a flow rate of 0.1-2 mL/min. The TOTAD interface allows solvent venting and the introduction of the analytes into the GC column. The proposed fully automated method allows the analysis of different groups of compounds (free sterols, tocopherols, squalene, and erythrodiol and uvaol) in one chromatographic run or the analysis of these compounds in different groups. Sensitivity is more than necessary, and repeatability is good, the CV ranging from 3 to 12% for the full analysis.
authors.affiliation: Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Cortés
authors.forename: Raquel
authors.initials: R
authors.lastname: Sanchez
authors.forename: Jesús
authors.initials: J
authors.lastname: Villén
authors.forename: Ana
authors.initials: A
authors.lastname: Vazquez
mesh_terms: D001322:Autoanalysis; D002849:Chromatography, Gas / Q000379:methods*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003201:Computers; D004042:Dietary Fats, Unsaturated / Q000032:analysis*; D015203:Reproducibility of Results; D012503:Saponins / Q000737:chemistry; D012680:Sensitivity and Specificity
chemical_list: D004042:Dietary Fats, Unsaturated; D012503:Saponins