Glycidyl fatty acid esters in food by LC-MS/MS: method development

摘要: An improved method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the analysis of glycidyl fatty acid esters in oils was developed. The incorporates stable isotope dilution (SIDA) quantifying five target analytes: palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2) and linolenic (C18:3). For analysis, 10 mg sample edible oil or fat is dissolved acetone, spiked with deuterium labelled analogs purified by a two-step chromatography C18 normal silica solid phase extraction (SPE) cartridges using methanol 5% ethyl acetate hexane, respectively. If concentration analytes expected to be below 0.5 mg/kg, g pre-concentrated first column. dried final extract re-dissolved 250 μL mixture methanol/isopropanol (1:1, v/v), 15 injected analytical LC column are eluted 100% methanol. Detection accomplished LC-MS/MS positive ion atmospheric pressure chemical ionization operating Multiple Reaction Monitoring mode monitoring 2 transitions each analyte. tested replicates virgin olive which free esters. detection limit calculated range 70-150 μg/kg analyte 1-3 oil. Average recoveries 5 at 10, 1 0.1 mg/kg were 84% 108%. major advantage our use SIDA all commercially available internal standards limits that lower factor 5-10 from published methods when used. Additionally, MS/MS chromatograms offer greater specificity than chromatography-mass operated selected mode. will applied survey food products Canadian market.