Preconcentration of seleno-amino acids on a XAD resin and determination in regional olive oils by SPE UPLC-ESI-MS/MS.
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.
Instituto de Química de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, CP 5700 San Luis, Argentina.
Sabier
S
Torres
Instituto de Química de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, CP 5700 San Luis, Argentina.
Soledad
S
Cerutti
Instituto de Química de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, CP 5700 San Luis, Argentina.
Julio
J
Raba
Instituto de Química de San Luis (INQUISAL-CONICET), Chacabuco y Pedernera, CP 5700 San Luis, Argentina. Electronic address: ppacheco@unsl.edu.ar.
Pablo
P
Pacheco
Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Almirante Brown 500, Chacras de Coria, CP 5505 Mendoza, Argentina. Electronic address: msilva@fca.uncu.edu.ar.
María Fernanda
MF
Silva
D002851:Chromatography, High Pressure Liquid; D057230:Limit of Detection; D000069463:Olive Oil; D010938:Plant Oils / Q000032:analysis*; D011137:Polystyrenes / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D017279:Selenocysteine / Q000031:analogs & derivatives* / Q000032:analysis; D012645:Selenomethionine / Q000032:analysis*; D052616:Solid Phase Extraction; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry / Q000379:methods
D000069463:Olive Oil; D010938:Plant Oils; D011137:Polystyrenes; D011145:Polyvinyls; D017279:Selenocysteine; C012101:XAD-4 resin; D012645:Selenomethionine; C002979:selenomethylselenocysteine
Olive oil; Seleno-amino acids; XAD® resin