QuEChERS-GC/MS联用技术测定羊杂碎中的N-二甲基亚硝胺

Determination of N-Dimethylnitrosamine in Haggis by QuEChERS Gas Chromatography Mass Spectrometry

采用Qu ECh ERS-气相色谱-质谱联用(gas chromatography-mass spectrometry,GC-MS)法建立测定榆林地区特色食品羊杂碎N-二甲基亚硝胺(N-nitrosodimethylamine,NDMA)的快速准确检测分析方法。羊杂碎样品前处理粉碎后经1%乙酸乙腈提取,利用MgSO_(4)和Na Cl (4︰1)作为盐析和脱水剂,经复合净化柱DPC净化检测,对比研究样品经水蒸气蒸馏提取,二氯甲烷反复萃取后,经无水硫酸钠脱水后在选择离子监测模式(selected ion monitoring,SIM)下检测NDMA含量。结果表明,羊杂碎中NDMA不同加标含量在不同前处理过程回收率差别明显,QuEChERS前处理样品NDMA回收率在67.5%~87.5%之间,明显高于水蒸气蒸馏法,同时检测过程存在较明显的基质效应。通过Qu ECh ERS-GC/MS联用方法,采用基质标准曲线检测羊杂碎中NDMA,其质量浓度在20~1 000 ng/mL范围内线性关系良好,相关系数为0.998 9,方法检出限(SLOD)和定量限(SLOQ)分别为0.8μg/kg和2.6μg/kg,加标回收率为78.6%~92.8%,SRSD为3.9%~7.2%(n=2)。该方法测定羊杂碎中NDMA优势明显,该方法简单、快速,净化效果好,灵敏度和准确率更高,可满足羊杂碎中NDMA的高效检测需求。

A rapid and accurate method for the determination of N-nitrosodimethylamine residues in haggis products was established using QuEChERS combined with gas chromatography-mass spectrometry.The sample of haggis was extracted with 1% acetic acid acetonitrile,with MgSO4 and NaCl(4︰1) used as salting out and dehydrating agents,purified and detected by DPC purification column.The sample was extracted by steam distillation,then extracted by dichloromethane,and dehydrated by anhydrous sodium sulfate.In the optimized chromatography and mass spectrometry condition,selected ion monitoring(SIM) pattern scanning was used to measure NDMA in haggis.The results showed that the recovery rate of NDMA in haggis had significant difference in different pre-treatment processes.The NDMA recovery rate of QuEChERS method ranged from 67.5% to 87.5%,which was significantly higher than that of steam distillation.At the same time,there was an obvious matrix effect in the detection process.DMA had a good linear relationship in the range of 20.0-1 000 ng/mL,and the correlation coefficient was 0.998 9.NDMA of haggis was detected by QuEChERS-GC-MS and matrix standard curve.The limits of detection(SLOD) and the limits of quantitation(SLOQ) were 0.8 μg/kg and 2.6 μg/kg.The recoveries were 78.6%-92.8%.The determination of NDMA in haggis had obvious advantages using QuEChERS gas chromatography-mass spectrometry method.This quantitative method was demonstrated to be rapid,simple,with good purification effect and high sensitive,which could be applied in the accurate determination of NDMA in haggiss.