小鼠器官中新型全氟化合物QuEChERs分析方法的建立与应用

Analysis of emerging per-and polyfluoroalkyl substances in mouse organs by QuEChERs

六氟环氧丙烷二聚体铵盐(HFPO-DA,商品名Gen X)和六氟环氧丙烷三聚体羧酸(HFPOTA)是目前最主要的全氟辛酸(PFOA)替代物.建立了以QuEChERs为核心的小鼠器官中HFPO-DA、HFPO-TA和PFOA的检测方法.小鼠器官样品经冻干粉碎后使用0.2%盐酸-乙腈溶液提取,混合N-丙基乙二胺、十八烷基键合硅胶和石墨化炭黑吸附剂做分散固相萃取净化,采用超高效液相色谱串联三重四极杆质谱检测.样品经C18色谱柱分离,1 mmol·L^(−1)乙酸铵水-甲醇溶液做流动相.结果表明,HFPODA、HFPO-TA和PFOA在5-500μg·L^(−1)的浓度范围内线性关系良好,相关系数均大于0.99.在5、10、100μg·kg^(−1)的3个添加水平下的平均回收率为64.8%-120%,相对标准偏差为0.6%-22.4%.不同小鼠器官中的最小检出量为0.016-0.077μg·kg^(−1),最低定量限为5.35×10^(−4)-2.55×10^(−3)ng.通过经口饲喂的方式将3种目标分析物暴露小鼠,应用已建立方法测定3种目标分析物在小鼠器官中的累积程度.检测发现,3种目标分析物总累积浓度次序为肝脏>肾脏>肺>心脏>大脑.各器官中HFPO-DA的累积浓度均显著(P<0.05)低于HFPO-TA和PFOA,说明相比较于HFPO-DA,PFOA和HFPO-TA有更强的生物富集潜力.

Ammonium hexafluoropropylene oxide dimer acid(HFPO-DA)and hexafluoropropylene oxide trimer acid(HFPO-TA)are the main alternatives for perfluorooctanic acid(PFOA).A QuEChERs-based novel method was established to simultaneously determine HFPO-DA,HFPO-TA,and PFOA in mouse organs.The mouse organs were extracted with a mixture of 0.2%HClacetonitrile,purified by dispersive solid-phase extraction with sorbents of N-propylethylenediamine,octadecyl bonded silica gel,and graphitized carbon black,and detected on ultra-performance liquid chromatography-tandem triple quadrupole mass spectrometry.The mixture of ammonium acetate aqueous solution(1 mmol·L^(−1))and methanol was used as the mobile phase,and the target analytes were separated with a C18 column.A calibration was performed for each analyte using the external matrix matched standards to eliminate the matrix effect.The matrix-matched calibration curves from 5μg·L^(−1)to 500μg·L^(−1)showed excellent linearity for all the analytes with R2≥0.99.The mean recoveries from mouse organs were 64.8%—120%with relative standard deviations of 0.6%—22.4%.The limit of detection and limit of quantitation for all the analytes were 0.016—0.077μg·kg^(−1)and 5.35×10^(−4)—2.55×10^(−3)ng.Mice were exposed to the target analytes by oral feeding.The accumulation of the 3 target analytes,measured by QuEChERs,was in the order of HFPO-TA>PFOA>HFPO-DA.The concentrations of HFPO-DA were significantly(P<0.01)lower than HFPO-TA and PFOA,indicating that HFPO-TA and PFOA have stronger bioaccumulation potential when compared with HFPO-DA.