加速溶剂萃取结合亲水液相色谱柱分离测定坚果中的8种生育酚异构体

Simultaneous and quick determination of all eight vitamin E isomers in nuts by accelerated solvent extraction and hydrophilic interaction liquid chromatography

目的建立加速溶剂萃取(ASE)结合亲水液相色谱(HILIC)柱分离测定坚果中8种生育酚异构体的方法。方法 2 g坚果样品经ASE提取富集后,用BEH Amide色谱柱(150 mm×3.0 mm,1.7μm)分离,以90%正己烷,10%叔丁基甲基醚-四氢呋喃-甲醇(20∶1∶0.1,V/V)作为流动相等度洗脱,荧光检测器激发波长294 nm,发射波长328 nm检测,外标法定量。结果 4种生育酚在0.5~80.0μg/ml、4种生育三烯酚在0.5~30.0μg/ml之间具有良好的线性(r^2>0.998),方法检出限在0.032~0.070 mg/kg之间,方法定量限范围0.096~0.210 mg/kg,三个水平加标回收率在87.5%~114.2%之间,6次重复测定相对标准偏差(RSD)均≤12%。结论本方法具有良好的灵敏度、回收率和重复性,适用于坚果中8种生育酚异构体的含量分布的测定。

Objective A method was developed for simultaneous quantification of eight E vitamers（ tocopherols and tocotrienols with α, β, γ and δ type） in nut matrix by hydrophilic interaction liquid chromatography（ HILIC） after pretreating with accelerated solvent extraction. Methods Nut samples were extracted using accelerated solvent extraction（ ASE）,the separation of 8 anlaytes was achieved using BEH amide amino column（ 150 mm × 3. 0 mm,1. 7 μm） and the mobile phase was 90% hexane and 10% methyl tert-butyl ether-tetrahydrofuran-methanol（ 20 ∶ 1 ∶ 0. 1,V/V）. Results The detection limits were ranged from 0. 032 to 0. 070 mg/kg with linear correlation coefficient above 0. 998, while quantification limits were 0. 096-0. 210 mg/kg. Intraday and interday recoveries of spiking standards were 87. 5%-114. 2%,and relative standard deviations（ RSDs） were all less than 12%. Conclusion The established method could be applied in the simultaneous detection of vitamin E isomers in nuts due to its excellent sensitivity,recovery and reproducibility.