Preconcentration of seleno-amino acids on a XAD resin and determination in regional olive oils by SPE UPLC-ESI-MS/MS

Food Chem. 2014 Sep 15:159:407-13. doi: 10.1016/j.foodchem.2014.03.045. Epub 2014 Mar 18.

Abstract

This study describes a method for seleno-amino acids determination in Argentinean olive oils. Preliminary total selenium determination in olive oils probed low concentrations (62.8±1.6 to 117.4±3.0 μg/kg) and the necessity of implementing a preconcentration method. To this end a XAD® resin was employed as sorbent for selenomethionine (Se-Met), selenomethylselenocysteine (Se-MetSeCys), and selenocysteine (Se-Cys) preconcentration. Determinations were performed by UPLC-ESI-MS/MS. Recoveries were between 84% and 97% for the seleno-amino acids studied, reaching a detection limit of 0.09 μg/kg, a precision of 10% (RSD, n=6), and an enhancement factor of 60-fold (6 for the extraction system and 10 for the preconcentration approach). The only detected Se species in the olive oils was Se-MetSeCys in concentrations ranging from 2.0 to 8.3 μg/kg.

Keywords: Olive oil; Seleno-amino acids; XAD® resin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography, High Pressure Liquid
  • Limit of Detection
  • Olive Oil
  • Plant Oils / analysis*
  • Polystyrenes / chemistry
  • Polyvinyls / chemistry
  • Selenocysteine / analogs & derivatives*
  • Selenocysteine / analysis
  • Selenomethionine / analysis*
  • Solid Phase Extraction
  • Spectrometry, Mass, Electrospray Ionization
  • Tandem Mass Spectrometry / methods

Substances

  • Olive Oil
  • Plant Oils
  • Polystyrenes
  • Polyvinyls
  • Selenocysteine
  • XAD-4 resin
  • Selenomethionine
  • selenomethylselenocysteine