顶空气相色谱法测定土壤中氯化苦残留

建立了一种快速测定土壤中氯化苦残留的方法。用石油醚室温下浸提土壤30 min后漩涡振荡,离心后取上清液直接采用顶空气相色谱法测定。结果显示,在质量浓度0.005 ~4 mg/L范围内,线性相关系数R2=0.999。氯化苦的添加水平在0.012 5 ~1.25 mg/kg范围内,5次重复的平均添加回收率在82.7% ~109.9%之间,相对标准偏差(RSD)在8.4% ~9.5%之间,检测限为0.008 8 mg/kg,定量限为0.029 mg/kg 。该方法可以满足土壤中氯化苦残留测定的要求。

Determination of Chloropicrin in Soil by Headspace Gas Chromatography

An effective and rapid analytical method for determination of chioropicrin residues in soil was developed.Chloropicrin in soil was extracted with petroleum ether by shaking for 30 min.The supernatant was transferred into a clear headspace vial after centrifugation and determined by headspace gas chromatography with ECD.The correlation coefficient at the concentration range of 0.005- 4 mg/L was 0.999.The average recoveries were 82.7%-109.9% at fortified concentration range of 0.012 5-1.25 mg/kg,with relative standard deviations(RSD) of 8.4%-9.5%.The limit of detection(LOD) was 0.008 8 mg/kg,The limit of quantitation(LOQ) was 0.029 mg/kg.The results showed that this method can be applied to determine the residues of chloropicrin in soil.