中文摘要：

建立了同位素稀释气相色谱/三重四极质谱法测定17种2,3,7,8位氯取代的二噁英同类物的痕量分析方法。使用Agilent 7000B三重四极气质联用仪,通过对色谱、质谱条件的优化,建立了高灵敏度和高选择性的二噁英同类物分析方法,17种二噁英毒性同类物的平均相对响应因子的相对标准偏差均小于11%;校正曲线在0.5～2000μg/L范围内显示良好线性。方法的检出限为0.05～0.34μg/L,满足PCDD/Fs的痕量分析需求。使用标准溶液样品进行定量检测的精密度测试,17种目标化合物的相对标准偏差均低于4%,方法重现性良好。将本方法应用于标准物质底泥样品的测定。底泥样品经加速溶剂提取、Power-PrepTM自动净化系统净化、浓缩后进样分析,采用多重反应监测方式（MRM）进行定性和定量分析。4种不同浓度底泥样品的检测结果在标准值范围,与高分辨质谱仪的测定结果无显著差异。由于三重四极质谱仪的购置及维护成本远低于高分辨质谱仪,本方法能降低二噁英同类物的分析成本。

英文摘要：

Gas chromatography coupled to triple quadrupole mass spectrometry（GC/MS/MS） has been developed for the ultratrace analysis of 17 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins（PCDDs） and dibenzofurans（PCDFs）.Main parameters of GC and MS/MS were optimized to improve the conditions of separation and resolution of target compounds.In multiple reactions monitor（MRM） mode,for each target compound two pairs of precursor ions and product ions were selected for qualitative and quantitative analysis.The average relative response factors（RRF） were calculated during a five-point calibration（0.5-2000 μg/L） for the 17 PCDD/F congeners.The relative standard deviations（RSD） of all congeners were below 11%.Low limits of detection from 0.05 to 0.34 μg/L for PCDD/Fs were obtained.Certified reference materials,including one solution sample and four sediment samples,were applied to confirm the analytical method.Before instrumental analysis,the sediment samples were extracted by accelerated solvent extraction,and then purified by Power-PrepTM automatic cleanup system.The RSDs of PCDD/Fs quantitation in the solution sample was less than 4%.The determination results of solution and sediment samples were in good agreement with the certified values.Consequently,the GC/MS/MS method could be used as an alternative to the relatively high-cost HRMS method for monitoring PCDD/Fs.