Determination of tocopherols in vegetable oils by CEC using methacrylate ester-based monolithic columns.
The separation and determination of tocopherols (Ts) in vegetable oils by CEC using methacrylate ester-based monolithic columns has been developed. The effects of pore size of the monolithic columns were studied, and the composition of mobile phase was optimized. The optimal pore size of the monolith was obtained with 12 wt% 1,4-butanediol in the polymerization mixture. Excellent resolution between tocopherols was achieved within 10 min analysis time with a 99:1 v/v MeOH-aqueous buffer containing 5 mM tris(hydroxymethyl)aminomethane at pH 8.0. The LODs were lower than 2.3 microg/mL, and interday and column-to-column reproducibilities at 25 microg/mL were better than 5.6%. Using a 93:7 v/v MeOH-aqueous buffer, both tocopherols and tocotrienols (T(3)s) of grapeseed and palm oils were resolved. Application to the detection of olive oil adulteration with low-cost edible oils was demonstrated.
Lerma-García
María Jesús
MJ
Department of Analytical Chemistry, Faculty of Chemistry, University of Valencia, Burjassot, Valencia, Spain.
Simó-Alfonso
Ernesto F
EF
Ramis-Ramos
Guillermo
G
Herrero-Martínez
José M
JM
D020374:Chromatography, Micellar Electrokinetic Capillary / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D008689:Methacrylates; D000069463:Olive Oil; D000073878:Palm Oil; D010938:Plant Oils / Q000737:chemistry* / Q000592:standards; D012639:Seeds / Q000737:chemistry; D024505:Tocopherols / Q000032:analysis*; D024508:Tocotrienols / Q000032:analysis; D027843:Vitis
D008689:Methacrylates; D000069463:Olive Oil; D010938:Plant Oils; D024508:Tocotrienols; D000073878:Palm Oil; D024505:Tocopherols