加压毛细管电色谱法同时测定植物油中4种抗氧化剂

Determination of four antioxidants in vegetable oils by pressurized capillary electrochromatography

采用加压毛细管电色谱-紫外检测,建立了一种适用于植物油中常见抗氧化剂的分离检测方法。使用1.8μm粒径的C18毛细管色谱柱,以乙腈-水（0.05%甲酸）为流动相进行梯度洗脱,泵流速为0.05mL/min,分流比为1∶200,分离电压为15k V,没食子酸丙酯（PG）、叔丁基对苯二酚（TBHQ）、丁基羟基茴香醚（BHA）、2,6-二叔丁基对甲酚（BHT）四种抗氧化剂可在8min内实现快速分离。各组分的检出限（S/N=3）分别为0.6、2.0、3.0、5.5μg/mL,线性关系良好,样品加标回收率在93.5%～108.0%之间,RSD在0.3%～1.3%之间。将所建立方法应用于植物油样品的分析,取得了良好的分析结果。

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（ pH3.2） at a pump flow rate of 0.05 mL / 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 / mL 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%.