衍生化气相色谱法测定土壤中萘乙酸和萘乙酸钠

摘要

To determine the contents of naphthylacetic acid and sodium naphthalene acetate content in soil by derivative gas chromatography.Dichloromethane was used as extracting solution.The extract was analyzed by gas chromatography with FID detector and quantified by external standard method.The results showed that the calibration curve of chromatographic peak area was linear over the concentration of naphthylacetic acid in the range of 1～20 mg/L.The limit of detection(LOD)of naphthylacetic acid in soil was 0.33 mg/kg.The recoveries of naphthylacetic acid in soils sample for addition of 1.00 mg/kg and 4.00 mg/kg were 85.1％and 91.2％,respectively with RSDs of 8.9％and 7.2％.The limit of detection(LOD)of sodium naphthalene acetate in soil was 0.40 mg/kg.The recoveries of sodium naphthalene acetate in soils sample for addition of 1.20 mg/kg and 4.80 mg/kg were 82.1％and 88.6％,respectively with RSDs of 9.7％and 8.2％.The method with sensitivity,accuracy and precision was conformed to the requests of pesticides residues detection technologies.%采用衍生化气相色谱法测定土壤中萘乙酸和萘乙酸钠的含量.采用二氯甲烷为提取溶剂,通过三氟化硼-甲醇快速甲酯化,气相色谱分离,FID 检测器测定,外标法定量.萘乙酸的质量浓度在1～20 mg/L范围内与色谱峰面积呈良好的线性关系.萘乙酸在土壤中的检出限为0.33 mg/kg、土壤中的添加水平为1.00 mg/kg、4.00 mg/kg,回收率为85.1％、91.2％,相对标准偏差为8.9％、7.2％.萘乙酸钠在土壤中的检出限为0.40 mg/kg、土壤中的添加水平为1.20 mg/kg、4.80 mg/kg,回收率为82.1％、88.6％,相对标准偏差为 9.7％、8.2％.该方法的灵敏度、准确度和精密度均符合农药残留检测技术的要求.