固相萃取-气相色谱-负化学源质谱法测定人血清中的多溴联苯醚

采用OasisHLB固相萃取柱萃取血清中的多溴联苯醚(PBDEs),经浓硫酸柱上除脂后,利用气相色谱-负化学源质谱法测定BDE-17、28、47、66、99、100、153、154、183和209共10种PBDEs组分。BDE-209的测定采用DB-5 ms色谱柱(15 m×0.25 mm×0.1 μm),其他组分采用VF-5 ms色谱柱(30 m×0.25 mm×0.25 μm)。对样品中蛋白质的去除溶剂和固相萃取条件(如洗脱溶剂及其用量)进行了优化。胎牛血清中的加标回收试验结果显示,各PBDEs单体相对于内标的平均回收率为78.5%～109.7%,日内测定的相对标准偏差(RSD)为0.3%～7.4%,日间测定的RSD为1.4%～14.1%。胎牛血清中三溴～七溴联苯醚的检出限(信噪比为3)为0.10～0.27 ng/L;定量限(信噪比为10)除了BDE-209为7.91 ng/L外,其他PBDEs为0.35～0.91 ng/L。采用本方法测定标准参考物质SRM1957和SRM1958,结果在参考值范围内。实验结果表明,本方法灵敏度高、准确度和精密度好,简便快速,溶剂消耗量少,适用于人体血清中三至十位溴取代联苯醚的测定。

Determination of polybrominated diphenyl ethers in human serum using solid-phase extraction and gas chromatography coupled with negative chemical ionization mass spectrometry

A simplified analytical method comprised of solid-phase extraction (SPE) and gas chromatography coupled with negative chemical ionization mass spectrometry (GC-NCI/MS) has been developed for the determination of 10 polybrominated diphenyl ethers (PBDEs) congeners in human serum. After the extraction by Oasis HLB custom-made SPE cartridges, the lipids in serum were decomposed by concentrated sulfuric acid directly added on the SPE column. The solvent for protein cleanup and the SPE conditions, such as elution solvent and its volume were optimized. The recoveries of the PBDEs spiked in fetal bovine serum relative to internal standards were in the range of 78.5% - 109.7% at five spiked levels (three spiked levels for BDE-209). The intra-day relative standard deviations (RSDs) were between 0.3% and 7.4%, while the inter-day RSDs were between 1.42% and 14.1%. The limits of detection (LOD, S/N = 3) and the limits of quantification (LOQ, S/N = 10) were in the range of 0.10 - 0.27 ng/L and 0.35 -0.91 ng/L respectively for all PBDEs, except BDE-209. The LOQ (blank concentration value x 3) for BDE-209 was 7.91 ng/L. The method was verified by accurate analysis of organic contaminant standard reference materials (SRM) 1957 and 1958. The results indicated that the proposed method is sensitive, accurate, fast, simple, low solvent consumption and suitable for the determination of tri- to deca-BDE in human serum.