QuEChERS-超高效液相色谱-质谱法测定葡萄中代森锰锌动态残留研究

Determination of Dynamic Residues in Grape by QuEChERS-HPLC-MS/MS

根据超高效液相色谱-串联质谱检测葡萄中代森锰锌的分析方法,用QuEChERS方法对葡萄样品中的代森锰锌进行提取和净化,并运用超高效液相色谱-串联质谱在多反应离子监测模式下对样品进行检测。碎片离子对m/z 241.2/117、241.2/134进行定性分析、m/z 241.2/193进行外标法定量分析。结果表明:喷施代森锰锌后,400倍液和600倍液剂量在葡萄上原始沉积量分别为15.78、11.56 mg/kg,在葡萄上施药后第15天,代森锰锌降解率分别为95.47%、94.29%,降解半衰期为2.45、2.42 d,代森锰锌在葡萄上的消解符合一级动力学特征。

According to the determination of mancozeb in grape by HPLC-MS/MS,the QuEChERS method was used to extract and purify mancozeb in grape samples,and the samples were detected by HPLC-MS/MS under multi-reaction ion monitoring mode.The fragment ions were used for qualitative analysis of m/z 241.2/117 and 241.2/134,and the external standard method was used for quantitative analysis of m/z 241.2/193.Finally,it was concluded that after spraying mancozeb,the initial deposition amount of 400 times liquid and 600 times liquid on grape was 15.78 mg/kg and 11.56 mg/kg,respectively;the degradation rate of mancozeb was 95.47%and 94.29%respectively on 15 d after spraying;the degradation half-life was 2.45 d and 2.42 d,and the digestion of mancozeb in grape was in line with the first-order kinetic characteristics.