毛叶枣中多菌灵、吡虫啉和啶虫脒消解动态研究

Degradation Dynamics of Carbendazim, Imidacloprid and Acetamiprid in Ziziphus mauritiana

采用超高效液相色谱—串联质谱,研究了多菌灵、吡虫啉和啶虫脒在毛叶枣中的消解动态和最终残留量。毛叶枣样品经乙腈提取,低温冷冻液萃取后,采用正离子多反应监测模式(MRM)测定,结果表明:在0.1~10μg/L范围内,3种农药的线性关系良好,检出限为0.06μg/kg,定量限为0.20μg/kg,回收率范围为89.1%~97.0%,相对标准偏差为5.3%~6.9%。田间试验结果表明,多菌灵、吡虫啉和啶虫脒在毛叶枣中的消解半衰期分别为3.2、3.3、2.8d,最终残留试验结果表明,在毛叶枣采收期时3种农药均有低含量检出,表明3种农药在毛叶枣上的残留时期较长,喷施时需控制好喷施浓度和间隔期。

An ultra high performance liquid chromatography-tandem mass spectrometry method was developed to study the degradation dynamics and final residues of carbendazim, imidacloprid and acetamiprid in Z. mauritiana. The Z. mauritiana samples were extracted by acetonitrile, extracted by cryogenic liquid-liquid extraction. Under positive ion ionization and multiple reaction monitoring, the results showed that there was a good linear relationship in the range of 0.1 μg/L to 10 μg/L, the limits of detection and quantification of the method was 0.06 μg/kg and 0.20 μg/kg, respectively. The average recoveries was in the range of 89.1% to 97.0% with the relative standard deviations from 5.3% to 6.9%. The results of field experiments showed that the half life of carbendazim, imidacloprid and acetamiprid was 3.2 d, 3.3 d and 2.8 d, correspondingly. The final residue test results showed a low content of carbendazim, imidacloprid and acetamiprid in the Z. mauritiana after harvest. The results showed long residue time of carbendazim, imidacloprid and acetamiprid in the Z. mauritiana, and the spraying concentration and safe interval should be seriously considered.