QuEChERS-气相色谱-四极杆飞行时间质谱筛查大米中有机磷阻燃剂残留  

Screening of organophosphorus flame retardant residues in rice by QuEChERS⁃gas chromatography⁃quadrupole time⁃of⁃flight mass spectrometry

作　　者：李康聪 杨吉双 李秀琴[1] 高燕 张庆合[1] LI Kangcong;YANG Jishuang;LI Xiuqin;GAO Yan;ZHANG Qinghe(Division of Chemical Metrology and Analytical Science,National Institute of Metrology,Beijing 100029,China;China Academy of Information and Communications Technology,Beijing 100183,China)

机构地区：[1]中国计量科学研究院化学计量与分析科学研究所,北京100029 [2]中国信息通信研究院,北京100083

出　　处：《色谱》2023年第11期1021-1029,共9页Chinese Journal of Chromatography

基　　金：国家自然科学基金青年科学基金项目(22006145).

摘　　要：基于QuEChERS⁃气相色谱⁃四极杆飞行时间质谱(GC⁃Q⁃TOF/MS)建立了大米中21种有机磷阻燃剂(OPFRs)的筛查方法,并对不同地区大米样品中的OPFRs残留情况进行分析。首先对21种OPFRs混合标准溶液(含量为0.1μg/g)进行GC⁃Q⁃TOF/MS全扫描(扫描范围m/z 50~450),之后对21种OPFRs的裂解机理进行研究,获得化合物的保留时间、同位素丰度比、特征碎片分子式以及精确质量数等信息,建立OPFRs的标准谱库;采用QuEChERS方法对大米样品进行提取和净化,选择DB⁃5MS UI色谱柱,在优化的升温程序条件下,21种OP⁃FRs在16 min内可完成色谱分离;在特征碎片离子数量≥2、精确质量窗口为±2×10^(-5)(±20 ppm)、保留时间偏差为±0.2 min、离子丰度偏差小于20%的条件下,利用解卷积软件对样品全扫描数据进行分析,实现了大米样品中21种OPFRs的筛查。结果表明,对于烷基类和芳香类OPFRs,将加标水平从2 ng/g提升至10 ng/g时,检出率可分别提升22%和25%;在2 ng/g的加标水平下,氯化类OPFRs中仅磷酸三(2⁃氯异丙基)酯(TCIPP)未被检出,说明该类OPFRs即使在低浓度情况下也相对容易被确认。采用所建立的分析方法对不同地区的实际大米样品进行测定,共检出11种OPFRs,其中磷酸三甲酯(TMP)、磷酸三(异丁基)酯(TiBP)、磷酸三(3,5⁃二甲基苯基)酯(T35DMPP)的检出率最高,且不同地区大米样品中的OPFRs种类存在一定差异。本方法利用GC⁃Q⁃TOF/MS技术实现了大米样品中OPFRs的鉴定,为复杂基质样品中OPFRs的准确筛查提供了参考。Organophosphorus flame retardants(OPFRs)have emerged as good alternatives to brominated flame retardants,the use of which is globally restricted.In this study,a screening method based on QuEChERS⁃gas chromatography⁃quadrupole time⁃of⁃flight mass spectrometry(GC⁃Q⁃TOF/MS)was established for the determination of 21 OPFRs in rice.First,full scan(scanning range,m/z 50-450)was performed with a mixed standard solution of the 21 OPFRs(0.1μg/g)by GC⁃Q⁃TOF/MS.The fragmentation pathways of these OPFRs were then investi⁃gated to explore their cleavage fragments,the interrelationships among fragments,and the pos⁃sible cleavage modes of alkylated,chlorinated,and aromatic OPFRs.The retention times,iso⁃topic abundance ratios,and molecular formulas of the characteristic fragments as well as the exact mass of the compounds were obtained to establish a mass spectral library of the OPFRs.Rice samples were extracted and purified by the QuEChERS method,and 0.5%formate aceto⁃nitrile solution was used as the extraction solvent;4 g of magnesium sulfate,1 g of sodium chloride,0.5 g of disodium hydrogen citrate,and 1 g of sodium citrate as the extraction⁃salt combination;and 50 mg of primary secondary amine(PSA),50 mg of octadecylsilane(C18),and 150 mg of magnesium sulfate as the purification materials.The chromatographic separation of the 21 OPFRs was completed within 16 min under optimized temperature program conditions on the DB⁃5MS UI column.The screening parameters were optimized,and a full scan of the samples was performed under the following conditions:number of characteristic fragment ions≥2;accurate mass window=±2×10^(-5)(±20 ppm);retention time deviation=±0.2 min,and ion abundance deviation<20%.The developed method was applied to the screening 21 OPFRs in the samples.The results indicated that the matrix interference was greatly reduced by decreasing the extraction accurate mass window,thereby improving the signal⁃to⁃noise ratio of the ana⁃lytes.The targets were extracted from the matrix

关 键 词：QUECHERS 气相色谱⁃四极杆飞行时间质谱 有机磷阻燃剂 筛查数据库 大米 

分 类 号：O658[理学—分析化学]