中文摘要：

采用固相萃取（solid phase extraction, SPE）柱对样品中维生素B12进行浓缩与净化,提出了一种可灵敏测定营养强化食品中维生素B12含量的超高效液相色谱-串联质谱（ultra high performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS）方法,并通过实验考察了不同固相萃取柱对维生素B12含量测定结果的影响.实验结果表明,采用HLB（hydrophile-lipophile balance number）固相萃取柱进行富集与净化,维生素B12在0.5～100.0μg/L浓度范围内与其响应值呈良好的线性关系,检出限为1.0μg/kg,说明该方法具有分析速度快、灵敏度高、重复性好的优点,适用于对营养强化食品中维生素B12含量的测定.

英文摘要：

A simple, fast and accurate method for determination of vitamin B12 in fortified foods is developed using ultra high performance liquid chromatography-tandem mass spec-trometry （UPLC-MS/MS）. The sample is concentrated by solid phase extraction （SPE） column. The linear range of the method is from 0.5 to 100.0 μg/L with a correlation co-efficient of 0.999 9. The detection limit is 1.0 μg/kg. The proposed method exhibits high sensitivity and good reproducibility for determining vitamin B12.