正相高效液相色谱法测定食物中8种维生素E异构体及维生素A

建立了正相高效液相色谱测定食物中8种维生素E异构体及维生素A的方法。样品中的维生素E异构体和维生素A经皂化和液液萃取,Waters ACQUITY^TM UPLC BEH Amide色谱柱(150 mm×3.0 mm, 1.7 μm)分离,体积比为90 : 10的正己烷与叔丁基甲基醚-四氢呋喃-甲醇(20:10:1, v/v/v)为流动相,荧光检测器和紫外检测器串联检测。4种生育酚在5.0~60.0 mg/L(r²≥0.9999)、维生素A和4种三烯生育酚在0.5~6.0 mg/L(r²≥0.9996)范围内具有良好的线性,各基质中目标物的检出限在20~60 μg/kg之间;9个组分在各基质中的加标回收率为79.2%~114.2%,相对标准偏差(RSD)为1%~12%。该方法简便、灵敏、可靠、环保,可用于食物中8种维生素E异构体以及维生素A含量的同时测定。

Simultaneous determination of eight vitamin E isomers and vitamin A in foods by normal-phase high performance liquid chromatography

A synchronous detection method was established by normal-phase (NP)-HPLC to separate and determine eight vitamin E isomers and vitamin A in foods. The sample was pretreated and then separated on a Waters ACQUITY^TM UPLC BEH Amide column (150 mm×3.0 mm, 1.7 μm). The mobile phase consisted of hexane (A, 90%) and tert-butyl methyl ether-tetrahydrofuran-methanol (20 : 10 : 1, v/v/v) (B, 10%). The analytes were detected by UV and fluorescence detectors, identified and quantified with external standards. The linear ranges of tocopherols were from 5.0 mg/L to 60.0 mg/L (r²≥0.9999), and those of tocotrienols and vitamin A were from 0.5 mg/L to 6.0 mg/L (r²≥0.9996), while the LODs of vitamin E isomers and vitamin A were from 20 μg/kg to 60 μg/kg. The method is of high precision, stability and repeatability, and the recoveries were from 79.2% to 114.2%. This method is simple, accurate and suitable for the analysis of vitamin E isomers and vitamin A in foods.