液相色谱串联质谱法测定婴幼儿食品中维生素D3的质量浓度

摘要

建立了同位素内标液相色谱串联质谱法测定婴幼儿食品中维生素D3质量分数.试样加同位素内标后,乙醇-50％氢氧化钾溶液皂化,石油醚萃取,Atlantis T3色谱柱(100 mm×2.1 mm,3μm),甲醇-5 mmol/L甲酸胺溶液作为流动相,梯度洗脱进行液相分离,采用电喷雾正离子方式,多反应选择离子监测,内标法峰面积定量.婴幼儿食品中维生素D3质量浓度在2～200 μg/L范围内线性良好,相关系数r均大于0.99,配方奶粉和米粉在10,50和100 μg/kg三个质量分数水平的添加回收率分别为86.1％～107％和86.2％～106％,变异系数分别为4.48％～7.08％和2.10 ％～4.26％(n=6).方法的定量限为10 μg/kg.方法简便、准确,适用于婴幼儿食品中维生素D3的检测.%To develop a isotope-labeled internal standard liquid chromatography tandem mass spectrometry(LC-MS/MS)method for the determination of vitamin D3 in foods for infants and young children.The sample was inoculated with a isotope-labeled internal standard and saponified with ethanol-50 ％ potassium hydroxide,followed by extraction with petroleum ether.The chromatographic separation was performed on the Adantis T3 column (100 mm× 2.1 mm,3 μm),using methanol-5 mmoL/L ammonium formate solution as the mobile phase by gradient elution.The method applied positive electrospray ionization and multiple reaction monitoring mode and quantified with peak area with internal standard method.A good linearity was obtained for 2～2000 μg/L with a correlation coefficient above 0.99.The average recoveries from three different were with the range of 86.1％ to 107％ and 86.2％ to 106％ respectively in formula and rice flour at spiked levels of 10,50,100 μg/kg.and the relative standard deviations were between 4.48 ％ to 7.08 ％ and 2.60 ％.to 4.26 ％ respectively(n=6).The limit of quantification was 10 μg/kg.This method is simple,accurate and suitable for determination of vitamin D3 in foods for infants and young children.