QuEChERS-同位素稀释-气相色谱-串联质谱法测定动物源性食品中9种N-亚硝胺类化合物  

Determination of nine N-nitrosamines in animal derived foods by QuEChERS-isotope dilution combined with gas chromatography-tandem mass spectrometry

作　　者：孔祥一 庄丽丽 方恩华 林鹏[1] 郑子龙 郑向华 徐敦明 KONG Xiangyi;ZHUANG Lili;FANG Enhua;LIN Peng;ZHENG Zilong;ZHENG Xianghua;XU Dunming(Fisheries College of Jimei University, Xiamen 361021, China;Xiamen Customs Technology Center, Xiamen 361000, China;Fujian Administration for Market Regulation, Fuzhou 350003, China)

机构地区：[1]集美大学水产学院,福建厦门361021 [2]厦门海关技术中心,福建厦门361000 [3]福建省市场监督管理局,福建福州350003

出　　处：《色谱》2021年第1期96-103,共8页Chinese Journal of Chromatography

基　　金：国家重点研发计划(2019YFC1605400);食品安全国家标准项目(spaq-2019-40);福建省自然科学基金项目(2017J01020).

摘　　要：建立了同时测定动物源性食品中9种N-亚硝胺类化合物的气相色谱-串联质谱分析方法。当下动物源性食品中N-亚硝胺类化合物污染种类较多,对人体危害较大,但国标GB 5009.26-2016仅针对N-二甲基亚硝胺的检测,且存在样品前处理复杂、标准方法回收率低、再现性差等问题,因此建立同时快速检测多种N-亚硝胺类化合物的方法有一定现实意义。称取10.0 g样品,置于50 mL离心管中,加入200μL内标工作液和10 mL乙腈,冷冻30 min后,加入4 g硫酸镁和1 g氯化钠进行脱水,以9000 r/min离心5 min。取5 mL上清液使用150 mg聚苯乙烯二乙烯苯(PLS-A)粉末净化,再使用1.6 g MgSO4和0.4 g NaCl脱水,过0.22μm滤膜,上机分析。在初始温度为50℃时采用程序升温模式,0.16 min后,以900℃/min的速率将温度升至220℃。采用毛细管气相色谱柱HP-Innowax(30 m×0.25 mm×0.25μm)分离,使用电子轰击电离(EI)源检测,在多反应监测模式下,以保留时间和特征离子对信息进行定性和定量分析,使用内标法定量N-亚硝胺类化合物。结果表明,N-亚硝胺类化合物在0.1~50.0μg/L范围内具有良好的线性关系,方法的检出限(S/N=3)和定量限(S/N=10)分别为0.03~0.30μg/kg和0.10~1.00μg/kg。对不同样品基质进行0.5、1.0、3.0μg/kg3个水平的加标回收试验,9种N-亚硝胺类化合物的回收率为80.4%~98.5%,RSD(n=6)为2.41%~12.50%。应用建立的方法检测市面上常见的动物源性食品,除N-亚硝基乙胺、N-亚硝基吗啡胆碱外,其他7种N-亚硝胺类化合物均有不同程度检出。检测结果表明,腌制水产品中N-亚硝胺类化合物含量普遍高于其他样品。研究建立的方法操作简单,不需要长时间蒸馏提取,可快速对动物源性食品中N-亚硝胺类化合物进行定性和定量分析,且样品和试剂的消耗量更少,节省成本,对环境污染小。该法的建立对我国动物源性食品中N-亚硝胺类化合物残留水平的控制、检测标准In this study,a comprehensive analytical method based on gas chromatography-tandem mass spectrometry(GC-MS/MS)was developed for the determination of nine N-nitrosamines in animal derived foods.There are many kinds of N-nitrosamines in foods that are harmful to human health.However,the national standard GB 5009.26-2016 pertains only to the detection of N-dimethylnitrosamine;there are many drawbacks of this method,such as complicated sample preparation,low recovery rate,and poor reproducibility.Hence,it is of practical significance to establish a method for the simultaneous determination of a variety of N-nitrosamines.The optimal extraction conditions for the developed method were as follows:10.0 g aliquots of the sample were placed in a 50 mL centrifuge tube,followed by the addition of 10 mL acetonitrile and 200μL internal working standard solutions.After 30 min of freezing treatment,4 g magnesium sulfate and 1 g sodium chloride were added for dehydration,and the tube was centrifuged at 9000 r/min for 5 min.After vortex centrifugation,5 mL of the clear supernatant was purified using 150 mg polystyrene divinylbenzene(PLS-A).The purified extracts were dewatered using 1.6 g MgSO4 and 0.4 g NaCl,and then filtered through a 0.22μm membrane filter unit prior to GC-MS/MS analysis.Temperature-programmed was applied at an initial temperature of 50℃.After 0.16 min,the temperature was raised to 220℃at the rate of 900℃/min for 5 min.N-Nitrosamines were separated on an HP-Innowax column(30 m×0.25 mm×0.25μm).Identification and quantification were achieved using an electron impact ion(EI)source in positive ion mode with multiple reaction monitoring(MRM).The internal standard method was used to quantify the N-nitrosamines.Under the optimal conditions,the correlation coefficients of the standard calibration curves were not less than 0.99 in the range of 0.1-50.0μg/L.The limits of detection were 0.03-0.30μg/kg(S/N=3),and limits of quantification were 0.15-1.00μg/kg(S/N=10).At spiked levels of 0.5,1.0,and 3.0μg/kg,the

关 键 词：气相色谱-串联质谱 QUECHERS N-亚硝胺类化合物 动物源性食品 

分 类 号：O658[理学—分析化学]