凝胶渗透色谱结合气相色谱-负化学源质谱法分析鱼肉及鱼油中的多溴联苯醚和得克隆阻燃剂

建立了凝胶渗透色谱(GPC)结合气相色谱-负化学源质谱(GC-NCI/MS)检测鱼肉及鱼油中8种多溴联苯醚(PBDEs)同系物及2种得克隆阻燃剂(DP)的分析方法。试样中加入内标物BDE-77和13C12-BDE-209后进行索氏提取,提取液经自动GPC系统除脂,多层硅胶层析柱净化后,在15 m长的毛细管气相色谱柱上分离,NCI/MS以选择离子监测方式检测目标化合物。以鱼肉样品为基质,当PBDEs的加标水平为0.2 ng/g和2 ng/g、BDE-209和DP的加标水平相应提高10倍时,其平均加标回收率为71.1%～121.4%,相对标准偏差为2.96%～13.31%(n=5);以信噪比(S/N)为3计算方法的检出限(LOD)为2.2～39.8 ng/kg。用该方法检测市售鱼肉及鱼油样品,其中多溴联苯醚总含量为2.18～15.93 ng/g,以BDE-209、BDE-47为主,两种DP均未检出。该方法准确、灵敏度高,能够满足富含脂质的动物性样品中痕量DP和PBDEs残留的分析要求。

Determination of polybrominated diphenyl ethers and dechlorane plus in fish and fish oil supplements by gel permeation hromatography coupled with gas chromatography-negative chemical ionization mass spectrometry

Polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) are two kinds of widely used organic flame retardants, and PBDE and DP residues have been found in both environment and biota. A method for the determination of 8 PBDEs and 2 DPs in fish and fish oil supplements was developed using auto gel permeation chromatography (GPC) coupled with gas chromatography-negative chemical ionization/mass spectrometry (GC-NCI/MS) in the selected ion-monitoring (SIM) mode on a 15 m capillary column. The sample added with BDE-77 and 13C12-BDE-209 as the internal standards was extracted using a Soxhlet extractor, and further purified by auto GPC and a multilayer silica gel column. The sample preparation procedure was optimized, and the characteristic ions and fragmentations of the analytes in NCI/MS were studied. The limits of detection (LODs, S/N = 3) ranged from 2.2 to 39.8 ng/kg. The average recoveries were between 71.1% and 121.4% at two spiked levels of 2 and 20 ng/g for both BDE-209 and DP and 0.2 and 2 ng/g for others with the relative standard deviations between 2.96% and 13.31%. The developed method has been successfully applied in the determination of PBDEs and DPs in several fish and fish oil supplements samples. The total PBDEs found ranged from 2.18 to 15.93 ng/g, and DP was not found. This method was validated to be accurate and sensitive for the trace analysis of PBDEs and DPs in the samples with fat.