【摘要】 建立了人参根、茎、叶及土壤中腈菌唑的液相色谱-串联质谱检测方法,并研究了25%腈菌唑水分散粒剂在人参根、茎、叶和土壤中的消解动态及最终残留量。样品经丙酮提取,N-丙基乙二胺(PSA)固相萃取柱净化后,经Kromasil Eternity-5-C18(2.1 mm×150 mm,5μm)色谱柱分离,以乙腈和0.1%甲酸水溶液为流动相进行洗脱,采用质谱正离子扫描,多反应监测模式进行定量分析,外标法定量。在0.01~0.20 mg·kg-1添加范围内,回收率为80.9%~90.7%,相对标准偏差为5.54%~9.29%,定量限为0.005 mg·kg-1。该方法精密度高,重复性好,检出限低,能满足生产上对腈菌唑检测分析的要求。施药剂量为1 152 g·hm-2(以有效成分含量计)时,腈菌唑在人参根、茎、叶和土壤中的降解半衰期为6.25~9.94 d。施药剂量为576~1 152 g·hm-2时,腈菌唑在人参根、茎、叶和土壤中的最终残留量分别为未检出~0.060 1 mg·kg-1,未检出~0.081 7mg·kg-1,0.006 0~0.102 2 mg·kg-1和未检出~0.037 6 mg·kg-1。建议我国腈菌唑在干人参中的最大残留限量值分别为0.10 mg·kg-1,安全间隔期为35 d。更多还原

【Abstract】 A high performance liquid chromatography coupled with tandem mass spectrometry(HPLC-MS/MS) method was developed for determining degradation dynamics and final residues of myclobutanil 25% WG in ginseng root,stem,leaf and soil. The samples were extracted with acetonitrile,cleaned-up with primary secondary amine(PSA) solid phase extraction cartridge,separated by Kromasil Eternity-5-C18(2.1 mm ×150 mm,5 μm) column with a gradient of acetonitrile and 0.1% formate in water as mobile phases,and analyzed with the multiple reaction monitoring(MRM) in positive ion mode by employing the external standard method.The average recoveries and the relative standard derivations(RSDs) of myclobutanil at the spiked level of 0. 01-0. 20 mg·kg-1were80. 9%-90. 7% and 5. 54%-9. 29%,respectively,and the limit of quantification( LOQ) was 0. 005 mg·kg-1. The method with good reproducible,high precision and low detection limit could meet the requirements of residual analysis on ginseng production. The half-lives of myclobutanil were from 6. 25 days to 9. 94 days in ginseng root,stem,leaf and soil at spraying dosage of 1 152 g·hm-2.The final residues were below 0. 060 1 mg·kg-1in root,below 0. 081 7 mg·kg-1in stem,0. 006 0-0. 102 2 mg·kg-1in leaf and below 0. 037 6 mg·kg-1in soil at spraying dosage range from 576 to 1 152 g·hm-2. It is recommended that the MRLs of myclobutanil in dried ginseng may be suggested to be 0. 10 mg·kg-1temporarily,and the preharvest interval was set at 35 days.更多还原