液相色谱-串联质谱法测定强化食品中叶酸的含量  

Determination of Folic Acid in Fortified Foods by High Performance Liquid Chromatography-Tandem Mass Spectrometry

作　　者：王敬[1] 马育松[1] 刘彩虹[2] 艾连峰[1] 郭春海[1] 陈瑞春[1] 

机构地区：[1]河北出入境检验检疫局,河北石家庄050051 [2]中国检验检疫科学研究院,北京100123

出　　处：《分析测试学报》2014年第11期1224-1230,共7页Journal of Instrumental Analysis

基　　金：国家认监委制标项目(2009B537)

摘　　要：采用液相色谱-电喷雾电离串联质谱法测定强化食品（饮料、大米、奶粉、含乳饮料、饼干及果冻）中的叶酸含量。采用多种方法确保叶酸检测的准确性：1优化前处理操作步骤,并使用铝箔避光保存;2加入二丁基羟基甲苯（BHT）作为叶酸的抗氧化保护剂;3加入甲氨蝶呤作为内标物,抵消复杂基质的干扰。方法系统考察了提取条件对回收率的影响,并采用Waters HSS T3（2.1 mm×50 mm,1.7μm）反相色谱柱,以甲醇-10 mmol/L醋酸铵（p H 6.3）为流动相进行梯度洗脱分离,多反应监测（MRM）正离子扫描模式,以内标法进行定性和定量分析。该方法在0.05-100 ng/m L浓度范围内线性关系良好,定量下限为0.01-0.5 mg/kg,回收率为72.0%-109%,相对标准偏差（RSD）为3.8%-11.8%。该方法简单快速,灵敏度、准确度和精密度均能满足强化食品中叶酸的测定要求。A rapid, simple and sensitive method based on high performance liquid chromatography - tandem mass spectrometry（ HPLC -MS/MS） with an electrospray ionization（ESI） source was presen- ted for the analysis of folic acid in various fortified food products（ i. e. juice, rice, liquid infant milk, powder infant milk, biscuit and jelly）. Sensitivity and specificity of this method allowed three impor- tant results to be achieved： firstly, developing a rapid sample pretreatment that minimizes the analyte exposition to light, air and heat, eliminating any step of extract concentration and protection by alu- minum foil; secondly adding BHT（butylated hydroxytoluene） as antioxidant ; Finally, adding meth- otrexate as the internal standard. Effects of extraction conditions of different matrixes on recoveries were investigated. The sample was separated on a Waters HSS T3 column using methanol - 10 mmol/ L ammonium acetate （ pH 6. 3 ） as mobile phase by gradient elution, and analysed by MS with internal standard under multi -reaction monitoring （MRM） mode via positive electrospray ionization. The method indicated that the calibration curve showed a good linear relationship in the range of 0. 05 - 100 ng/mL, with quantitation limits of 0. O1 -0. 5 mg/kg in different matrixes. The recoveries were in the range of 72.0% - 109% , with RSDs of 3.8% - 11.8%. With the advantages of easy sample handling, high sensitivity and good precision, the method could meet the requirements for determina- tion of folic acid.

关 键 词：液相色谱-串联质谱 叶酸 强化食品 

分 类 号：O657.63[理学—分析化学] O563.8[理学—化学]