气相色谱-负离子化学电离质谱法分析深海鱼油 食品中的五种多溴联苯醚残留

建立了气相色谱-负离子化学电离质谱法(GC-NCI/MS)同时分析深海鱼油食品中5种多溴联苯醚残留的分析方法。深海鱼油食品用正己烷超声提取、中性与酸性硅胶色谱柱净化和正己烷洗脱后,以PCB103为内标物,采用GC-NCI/MS的选择离子监测方式(SIM)分析;同时探讨了5种多溴联苯醚的NCI/MS特征离子的断裂机理。当空白深海鱼油食品的加标浓度为20.0和100.0 μg/kg时,加标回收率为88.6%～111.3%,相对标准偏差为3.8%～13.5%,方法的检测限为0.77～1.34 μg/kg,线性范围为1.0～500.0 μg/kg,相关系数均大于0.9992。此方法已成功地应用于深海鱼油食品中5种痕量多溴联苯醚残留的同时分析。

Determination of Five Polybrominated Diphenyl Ether Residues in Deep-Sea Fish Oil Using Gas Chromatography-Negative Chemical Ionization/Mass Spectrometry

Polybrominated diphenyl ethers (PBDEs) are a kind of brominated flame retardants (BFRs), which refer to compounds used in some plastics to impede or even suppress the combustion process. As the emission or disposal of plastics, PBDE residues have been found in both environment and biota. In this work, an analytical method was developed for the simultaneous determination of 5 PBDE residues in deep-sea fish oil. PBDEs were extracted from deepsea fish oil with n-hexane, cleaned up on a silical gel column, and determined by using gas chromatography-negative chemical ionization/mass spectrometry (GC-NCI/MS) in the selected ion-monitoring (SIM) mode, with PCB103 as the internal standard. Meanwhile, the characteristic ion and fragmentation mechanism of some PBDEs in NCI/MS were evaluated. Recovery studies were performed at 20. 0 and 100.0 g/kg fortification levels for each PBDE, and the recoveries ranged from 88. 6% to 111. 3% with relative standard deviations between 3. 8% and 13.5% for different PBDEs. The limits of detection (LOD) were from 0.77 to 1. 34 1g/kg for different PBDEs. The developed method was linear over the range assayed, 1. 0 - 500. 0 g/kg, with correlation coefficients larger than 0. 999 2. The developed method has also been successfully applied to the determination of PBDEs in several deep-sea fish oil samples and the three most abundant PBDEs (PBDE-47, PBDE-99 and PBDE-100) were found.