全二维气相色谱-电子捕获检测器法分析土壤中毒杀芬同类物的残留

建立了全二维气相色谱-电子捕获检测器(GC× GC-μECD)检测土壤中毒杀芬同类物的分析方法.以非极性的DB- XLB(20 m×0.25 mm×0.25 μm)为第一色谱柱,中等极性的BPX-50(2 m×0.1 mm×0.1 μm)为第二色谱柱,对土壤中23种高关注毒杀芬同类物进行了分离鉴定,并采用基质曲线外标法进行定量分析.本方法在1～200,μg/L浓度范围内,毒杀芬同类物的线性相关系数(r2)均大于0.99,方法检出限(S/N=3)为0.039～0.482 μg/L,基质加标毒杀芬同类物的回收率为55％～115％,相对标准偏差(RSD)均小于30％(n=5).利用本方法对毒杀芬污染的土壤样品进行了测定,获得了较好的分离效果.

Comprehensive Two-dimensional Gas Chromatography with Micro-electron Capture Detector for Analysis of Toxaphene Congeners in Soil

A comprehensive two dimensional gas chromatography coupled with micro-electron capture detector(GC×GC-μECD) method for the simultaneous analysis of 23 congeners of toxaphene in soil has been developed and validated.A DB-XLB column(20 m×0.25 mm×0.25 μm) was chosen as the column for the first dimension,and a BPX-50 column(2 m×0.1 mm×0.1 μm) was chosen as the column for the second dimension.The matrix-matched external standard calibration curves were used for quantitative analysis.The established method showed good linearity with correlation coefficients(r2) higher than 0.99 in the concentration range of 1-200 μg/L.Limits of detection ranged from 0.039 to 0.482μg/L for individual congeners.The relative standard deviations(RSD) of all 23 toxaphene congeners in matrix spiked samples were below 30%(n=5),and recoveries ranged from 55% to 115%.For validation,the developed method was applied to the determination of toxaphene in a soil sample.