液相色谱-串联质谱法测定咀嚼片中B₁₂含量

Determination of vitamin B_(12) in chewable tablets by liquid chromatography-tandem mass spectrometry

目的建立液相色谱-串联质谱法(LC-MS/MS)测定多种维生素咀嚼片(儿童型)中维生素B12的分析方法,为维生素B12及其制剂的含量测定提供参考。方法样品中的维生素B12用10 mmol/L乙酸铵超声提取,三氯甲烷沉淀蛋白质,以10 mmol/L乙酸铵-甲醇作为流动相经SUPELCO DiscoveryHS C18柱(4.6 mm×150 mm,5μm)梯度洗脱分离,流速0.6 m L/min,采用LC-MS/MS在正离子模式下检测,外标法定量。结果 LC-MS/MS法在30~150 ng/m L范围内,维生素B12的浓度和峰面积的线性良好,相关系数r=0.993,精密度为2.4%,在不同的添加水平下,方法的回收率85.9%~95.7%,检出限为5 ng/g。结论液相色谱-串联质谱法简单快速、灵敏度高、准确性强,适用于保健食品中维生素B12的分析。

Objective To establish a method for determination of vitamin B12 in chewable multivitamins(childhood type) by liquid chromatography-tandem mass spectrometry(LC-MS/MS), and provide a reference for determination of vitamin B12 and its preparation. Methods Samples were ultrasonically extracted by 10 mmol/L ammonium acetate, and protein were precipitated by chloroform; then the samples were separated by SUPELCO Discovery HS C18 column(4.6 mm×150 mm, 5 μm)on a mobile phase of 10 mmol/L ammonium acetate-methanol as gradient elution solution, and the flow rate at 0.6 m L/min. LC-MS/MS was applied for the detection in the(ESI+)-MRM mode under the external standard method. Results The linear relationship between vitamin B12 concentration and peak area were good within 30~150 ng/m L range(r=0.993), and the precision was 2.4%; the recovery of different adding levels was 85.9%~95.7%, and the limit of quantification was 5 ng/g. Conclusion Liquid chromatography-tandem mass spectrometry method is simple, effective and sensitive, and it is applicable to the analysis of vitamin B12 in health foods.