反相高效液相色谱法同时测定植物油中四种生育酚

Simultaneous Determination of Four Tocopherols in Vegetable Oils by Reverse Phase High Performance Liquid Chromatography

建立了反相液相色谱法同时测定植物油中4种生育酚的方法。样品用甲醇超声提取,离心后取上清液氮吹至干,甲醇定容后过有机相滤膜,反相C30柱(4.6 mm i.d.×250 mm,5μm)分离,甲醇-水-叔丁基甲醚(60∶15∶25)作流动相等度洗脱,荧光检测(λex=290 nm,λem=340 nm)。结果表明,4种生育酚的质量浓度在0.050～100.0 mg/L范围内与峰面积呈良好的线性关系,线性相关系数(r2)大于0.999。在加标水平为0.50、50.0、500.0 mg/kg时,4种生育酚的平均加标回收率为81.3%～93.2%,相对标准偏差(RSD)小于6%,α-生育酚、β-生育酚、γ-生育酚及δ-生育酚的方法检出限(LOD)分别为0.10、0.05、0.05、0.02mg/kg。方法准确、灵敏、可靠,可应用于实际样品的分析。

A method for the simultaneous determination of four tocopherols in vegetable oils by reverse phase high performance liquid chromatography（RP-HPLC） was established.The sample was extracted with methanol under ultrasonic.The chromatographic separation was carried out on a C30 column（4.6 mm i.d.×250 mm，5 μm） using fluorescence detection at 290 nm of excitation wavelength and 340 nm of emission wavelength.Methanol-water-tert-butyl methyl ether（60∶15∶25）was used as mobile phase by isocratic elution.Results showed that good linear ranges for 4 tocopherols were obtained from 0.050 mg/L to 100.0 mg/L with correlation coefficients（r2）larger than 0.999.The mean recoveries were in the range of 81.3%-93.2% at three spiked levels of 0.50，50.0，500.0 mg/kg，and the relative standard deviations（RSDs） were less than 6%.The limits of detection（LODs） were 0.10 mg/kg for α-tocopherol，0.05 mg/kg for β- and γ-tocopherol，and 0.02 mg/kg for δ-tocopherol. The method is accurate，sensitive and reliable，and could be applied in the real sample analysis.