直接竞争ELISA法检测蔬菜中2,4-二氯苯氧乙酸

摘要

目的：研究竞争性酶联免疫法分析测定蔬菜中2,4-二氯苯氧乙酸(2,4-dichlorophenoxyacetic acid,2,4-D)残留量。方法样品用乙腈进行前处理后采用ELISA试剂盒检测蔬菜中2,4-D的残留,分析方法的灵敏度、回收率和稳定性；并比较其与超高效液相色谱-质谱法(ultra performance liquid chromatography-mass spectrometry, UPLC-MS)在灵敏度、稳定性等方法学参数上的差异。结果经过有机溶剂提取等前处理过程, ELISA与UPLC-MS的检测灵敏度分别可以达到1.739µg/kg和3µg/kg,回收率分别为80.19%~117.37%和80.04%~112.5%；试剂盒稳定性的测定证明其可以在4℃至少保存8个月。结论与UPLC-MS法相比,直接竞争 ELISA法简单、高效,检测快速,灵敏度高,适合大批量筛选样品。因此, ELISA法更加适合快速检测蔬菜中2,4-D的残留。%ABSTRACT:Objective To study the method for the rapid determination of 2,4- dichlorophenoxyacetic acid (2,4-D) in vegetables by direct competitive enzyme-linked immunosorbent assay (ELISA).MethodsThe samples were pretreated by acetonitrile, then the residual of 2,4-D in vegetables was detected by ELISA kit, and the sensitivity, recovery and stability of the method were analyzed. The sensitivity and stability of the method were compared with ultra performance liquid chromatography-mass spectrometry (UPLC-MS). Results By sample preparation, the limit of detection (LOD) of direct competitive ELISA and UPLC-MS method could reach to 1.739 µg/kg and 3 µg/kg respectively. The recovery rates were 80.19%~117.37% and 80.04%~112.5%. The stability result of the kit indicated that it could be preserved at 4℃ for more than eight months. Conclusion Compared with UPLC-MS method, direct competitive ELISA method is simple, efficient, fast, sensitive and suitable for screening of the mass samples. Therefore, the ELISA method is more suitable for rapid detection of 2,4-D in vegetables.