建立了大体积采样结合高分辨气相色谱-电子捕获负化学源-低分辨质谱(HRGC-ECNI-LRMS)测定空气中短链氯化石蜡(SCCPs)的定量分析方法。联合使用酸化硅胶复合层析柱和碱性氧化铝层析柱净化处理空气样品中的SCCPs,并对净化条件进行优化。使用该方法计算得到氯含量为58.1%~63.3%的SCCPs系列标准储备溶液的总响应因子与氯含量线性相关,相关系数(R2)大于0.99。该方法的仪器检出限(S/N≥3)为4.2 pg,定量限(S/N≥10)为12 pg。SCCPs的方法检出限(MDL)为0.34 ng/m3(n=7),实际样品加标回收率均达80%以上。该方法灵敏度高、选择性好,能满足空气样品中SCCPs的监测和分析需求。
An analytical method for quantifying short-chain chlorinated paraffins(SCCPs)in ambient air using high-volume sampling combined with high resolution gas chromatographyelectron capture negative ion-low resolution mass spectrometry(HRGC-ECNI-LRMS) was developed. An acidified silica gel column and a basic alumina column were used to optimize the cleanup procedures. The results showed a good linearity(R2〉0. 99)between the total response factors and the degree of chlorination of SCCPs in the content range of 58. 1%-63. 3%. The limits of detection(S / N ≥ 3)and the limits of quantification(S / N ≥ 10)were 4. 2 and 12 pg,respectively. The method detection limit(MDL)for SCCPs was 0. 34 ng / m3(n = 7). The recoveries of SCCPs in air samples were in the range of 81. 9% to 94. 2%. It is demonstrated that the method is suitable for the quantitative analysis of SCCPs in air samples.