Determination of four antioxidants in vegetable oils by pressurized capillary electrochromatography

A method for antioxidants analysis in vegetable oils was developed by using pressurized capillary electrochromatography( p CEC) with UV / Vis detection. The separations were performed on a C18 capillary column packed with 1.8μm particles. The mobile phase was acetonitrile / water containing 0.05% formic acid( p H3.2) at a pump flow rate of 0.05 m L / min with splitting ratio of 1 ∶ 200 and the separation voltage was 15 k V. Four antioxidants( PG,TBHQ,BHA,BHT) were baseline separated within 8min in gradient elution mode.The detection limits of each antioxidant( S / N = 3) were 0.6,2.0,3.0,5.5μg / m L respectively with good linear correlation.The method was applied to detect the regetable oils and the results was accurate. The spiked recoveries of vegetable oils were 93.5% ~108.0%,with RSD ranged 0.3% ~1.3%.