稳定同位素稀释/液相色谱-串联质谱法同时测定婴幼儿配方奶粉中5种脂溶性维生素

Simultaneous determination of 5 kinds of fat soluble vitamins in infant formula milk powder by stable isotope dilution/liquid chromatography-tandem mass spectrometry

中文关键词:  婴幼儿配方奶粉  脂溶性维生素  液相色谱-串联质谱法  同位素内标法

英文关键词:infant formula milk  fat soluble vitamins  liquid chromatography tandem mass spectrometry  isotope internal standard method

中文摘要:

      目的 建立稳定同位素稀释/液相色谱-串联质谱法同时测定婴幼儿配方奶粉中5种脂溶性维生素(VA、VD2、VD3、VE和VK1)的分析方法。方法 样品经皂化, 正己烷提取, 甲醇定容, 经ACQUITY UPLC BEH C18色谱柱(100 mm×2.1 mm, 1.7 μm)分离, 以0.2%甲酸水溶液和甲醇-乙腈(4:6, V:V)为流动相, 梯度洗脱, 采用正离子源电喷雾电离, 多反应监测模式测定, 同位素内标法定量。结果 VA、VD2、VD3、VE和VK1在一定浓度范围内具有良好的线性关系, 相关系数(r2)大于0.99, 检出限为0.2~5 ?g/100 g, 定量限为0.6~15 ?g/100 g。5种维生素的加标回收率为89.3%~109.2%, 相对标准偏差(relative standard deviation, RSD) 为3.82%~8.72% (n=6)。结论 本研究建立的方法在很大程度上简化了婴幼儿配方奶粉中脂溶性维生素的检测流程, 提高了实验效率和检测结果的准确性。

英文摘要:

      Objective To establish a method for the simultaneous determination of 5 kinds of fat soluble vitamins (vitamin A, vitamin D2, vitamin D3, vitamin E and vitamin K1) in infant formula milk powder by stable isotope dilution/liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methods The fat soluble vitamins were extracted with hexane and reconstituted with methanol after saponification. Then the sample was separated on an ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 μm) with 0.2% fomic acid solution and methanol-acetionitrile (4:6, V:V) as mobile phase by gradient elution. Mass spectrometry detection was performed in multiple reaction monitoring (MRM) mode with positive electrospray ionization. The quantification analysis was carried out by isotope dilution method. Results Vitamin A, vitamin D2, vitamin D3, vitamin E and vitamin K1 had good linear relationships in a certain concentration range with correlation coefficients (r2) above 0.99. The limits of detection of 5 kinds of vitamins were 0.2~5 ?g/100 g, and limits of quantitation were 0.6~15 ?g/100 g. The recoveries of 5 vitamins ranged from 89.3% to 109.2%, with relative standard deviations (RSD, n=6) of 3.82%-8.72% (n=6). Conclusion The established method greatly simplifies the determination process of vitamins in infant formula milk powder, and improves the efficiency and accuracy of the experiment results.