同位素稀释气相色谱/三重四极杆串联质谱法分析环境样品中的多氯萘

采用稳定同位素标记的多氯萘(PCNs)同类物为内标,建立了同位素稀释气相色谱/三重四极杆串联质谱技术测定环境样品中20种高关注的PCNs同类物的方法。结果表明:PCNs同类物的校正曲线在0.5~200 μg/L范围内线性良好(R²>0.99),检出限(LOD)为0.04~0.48 μg/L,相对标准偏差(RSD)小于15%。采用基质加标法评价该方法对实际环境样品中PCNs测定的回收率为45.2%~87.9%。为验证方法的适用性,以河流沉积物和再生铝冶炼排放的烟道气样品为对象,利用所建立的方法测定了20种PCNs同类物,并将结果与高分辨气相色谱/高分辨质谱方法的测定结果进行了比对,两种方法测定结果的RSD为0.5%~41.4%,表明所建立的同位素稀释气相色谱/三重四极杆串联质谱方法可用于实际环境样品中PCNs的定性、定量分析。

Determination of polychlorinated naphthalenes in environmental samples by isotope dilution gas chromatography-triple quadrupole mass spectrometry

An isotope dilution gas chromatography combined with triple quadrupole mass spectrometry (GC-MS/MS) method was established for the analysis of twenty polychlorinated naphthalenes (PCNs) congeners in environmental samples. The linear correlation coefficients (R²) of calibration curves were greater than 0.99 in the concentration range of 0.5-200 μg/L for all the twenty PCN congeners. The average relative response factors (RRF) were calculated based on a seven-point calibration for the twenty PCN congeners. The relative standard deviations (RSDs) of all the congeners were below 15% (n=7). The limits of detection (LOD) of the established method ranged from 0.04 to 0.48 μg/L for the twenty PCN congeners. The recoveries of matrix spiked samples ranged from 45.2% to 87.9%, and the RSDs ranged from 0.4% to 21.2%. The sediment samples and stack gas samples collected from secondary aluminum smelting were analyzed by the established method. The obtained results were also compared with the data analyzed by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) method. The comparison indicated that the data of the established method was in good agreement with those of HRGC/HRMS method with the RSDs of 0.5%-41.4%. Consequently, the established GC-MS/MS method can be applied to the determination of PCNs in environmental samples.