顶空气相色谱法测定土壤中氯化苦残留

Determination of Chloropicrin in Soil by Headspace Gas Chromatography

摘要: 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。

Abstract: 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.