基于凝胶渗透色谱及液相色谱串联质谱测定油脂性食品中的维生素A、D、E

本研究拟采用凝胶渗透色谱净化，建立液相色谱串联质谱联用测定油脂性食品中脂溶性维生素含量的新方法。对试验条件进行优化后发现，通过凝胶渗透色谱法以PT785 Bio-BeadsS-X3型为色谱柱，环己烷-乙酸乙酯（5:5，V/V）溶液为流动相，选择5 mL/min的流速进行样品前处理；在质谱分析部分采用电喷雾离子源（ESI）、正离子扫描方式，以多反应监测（MRM）进行定性定量分析能满足油脂性食品中维生素A、D、E含量测定的需求。实验表明：视黄醇、视黄醇醋酸酯、维生素D2、维生素D3、维生素E在5~200 μg/L的浓度范围内线性关系良好（相关系数r均在0.999以上），检出限分别为2 μg/kg、1 μg/kg、5 μg/kg、2 μg/kg、10 μg/kg；回收率为93.1%~l06.6%；相对标准偏差（n=6）1.09%~4.77%。该法具有准确度高、灵敏度高、分析周期短、操作简便等多重优势，适合油脂性食品中维生素A、D、E的测定。
The vitamins A, D and E in oil-rich foods were simultaneously determined using high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS), after purified with a gel permeation chromatography (GPC). The optimal extraction conditions were achieved on the PT785 Bio-BeadsS-X3 column, with a cyclohexane - ethyl acetate mixture at ratio of 5:5 (V/V) as the mobile phase. The optimal MS condition was positive electrospray ionization (ESI+)-MS method under multiple reaction monitoring (MRM) mode. The results indicate that retinol, retinol acetate, vitamin D2, vitamin D3, vitamin E were all in good linear relationship with correlation coefficient above 0.999 in the concentration range of 5-200 μg/L; the limit of detection of this method were 2 μg/kg, 1 μg/kg, 5 μg/kg, 2 μg/kg and 10 μg/kg respectively; the recovery rate at four spiked levels range from 93.1 to l06.6% with relative standard deviations (RSD, n = 6)above 1.09% and lower than 4.77%. The method is accurate, sensitive, rapid and easy, and can be applied to determine vitamins A, D and E in oil-rich foods.