气相色谱-负化学源质谱快速测定母乳中的多溴联苯醚

建立了母乳中8种多溴联苯醚(PBDEs：BDE28，BDE47，BDE99，BDE100，BDE153，BDE154，BDE183，BDE209)的气相色谱-负化学源质谱测定方法(GC-NCI/MS)。样品经索氏提取、酸化硅胶除脂、硅胶氧化铝色谱柱净化后,在7 m长的毛细管气相色谱柱上快速分离,NCI/MS以选择离子监测模式测定目标化合物。其中,三溴～七溴联苯醚采用内标法定量,十溴联苯醚(BDE209)采用同位素稀释法定量。8种PBDEs的检出限为1.74～6.35 pg/g(以脂肪计)。加标回收试验的回收率为61.5%～108%,相对标准偏差为2.06%～10.1%(n=6)。并采用母乳参考物质进一步证实了该方法的准确可靠。该方法提高了BDE209的分析灵敏度,而且分析成本相对较低,分析时间短,适于推广。

Fast determination of polybrominated diphenyl ethers in human milk using gas chromatography-negative chemical ionization/mass spectrometry

A method for the quantitative determination of 8 polybrominated diphenyl ethers (PBDEs) in human milk was established using gas chromatography-negative chemical ionization/mass spectrometry (GC-NCI/MS). After extraction by Soxhlet extractor, the lipid in the extract was removed by acidic silica, and the analyte was further purified by the multilayer silica-alumina column. The concentrations of BDE28, BDE47, BDE99, BDE100, BDE153, BDE154, BDE183 and BDE209 in human milk were fast determined by GC-NCI/MS in selected ion monitoring (SIM) mode on a 7 m column. The quantitative analysis was performed by isotope dilution method for BDE209 and internal standard method for other PBDEs. The limits of detection (LODs) of PBDEs in the lipid ranged from 1.74 to 6.35 pg/g. The recoveries of the spiked PBDEs were between 61.5% and 108% and their relative standard deviations (RSDs) (n=6) were between 2.06% and 10.1%. The method was further validated by the analysis of the reference materials of human milk. It was demonstrated that it is a low cost, rapid and reliable alternative for the trace analysis of selected PBDEs, especially for BDE209 in human milk