UPLC-MS/MS快速筛查婴幼儿配方乳粉中3种香兰素污染

Rapid Screening of Three Vanillin Contamination in Infant Formula by UPLC-MS/MS

文章建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)快速筛查婴幼儿配方乳粉中3种香兰素污染。通过对质谱条件、色谱条件和前处理条件进行试验和优化,采用水-乙腈(3:7,v/v)对样品进行溶解和萃取,经正己烷除脂和尼龙膜过滤净化,最终样液采用C18色谱柱分离,以0.1%(v/v)甲酸水和甲醇为流动相进行梯度洗脱,MRM模式测定,外标法定量,标准曲线比较法评估基质效应。结果表明,香兰素、乙基香兰素、甲基香兰素线性范围为5~160ng/mL;检出限分别为6.0、1.5、0.6μg/kg,定量限分别为20.0、5.0、2.0μg/kg;加标回收率分别为95.7%~105.1%、92.9%~103.5%、94.4%~107.1%;仪器精密度分别为5.98%、4.42%、2.46%,方法精密度分别为4.74%、3.34%、2.02%;基质效应评估表明,3种香兰素均无基质效应。该方法较国标方法和食品补充检验方法限值低、分析时间短、前处理简单,适用于婴幼儿配方乳粉中3种香兰素污染的快速筛查。

An ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) method was established to rapidly screen three kinds of vanillin contamination in infant formula milk powder. The conditions of mass spectrometry, chromatographic and pretreatment were tested and optimized. The samples were dissolved and extracted with water-acetonitrile(3∶7, v/v), and the extract was degreased by n-hexane and purified by nylon membrane filtration. The sample solution was separated by a C18chromatographic column, and 0.1%(v/v) formic acid water and methanol were used as mobile phases for gradient elution, the target compound were determined by MRM mode and quantified by external standard method. Matrix effects were assessed by standard curve comparison. The results showed that the linear range of vanillin, ethyl vanillin and methyl vanillin were 5~160 ng/mL;the detection limits were 6.0 μg/kg, 1.5 μg/kg, 0.6 μg/kg;the quantification limits were 20.0 μg/kg, 5.0 μg/kg,2.0 μg/kg;the recovery rates of standard addition were 95.7%~105.1%, 92.9%~103.5%, 94.4%~107.1%;the instrument precisions were 5.98%, 4.42%, 2.46%, and the method precisions were 4.74%, 3.34%,2.02%. The matrix effect evaluation showed that none of the three vanillins had matrix effect. Compared with the national standard method and the food supplement testing method(BJS), this method had lower limit value, shorter analysis time and simpler pretreatment, and is suitable for the rapid screening of three kinds of vanillin contamination in infant formula.