建立了采用固相萃取-液相色谱-串联质谱同时测定麦冬、玄参、延胡索中7种甲氧基丙烯酸酯类杀菌剂残留量的方法.样品经乙酸乙酯提取,氨基固相萃取柱净化后,经C18色谱柱分离,以甲醇和1.0‰甲酸溶液为流动相梯度洗脱,电喷雾正离子模式离子化,选择反应监测方式监测,串联质谱测定,外标法定量.结果显示,各目标物在1或2个数量级浓度范围内的线性关系良好,相关系数均大于0.996.醚菌胺、啶氧菌酯和肟菌酯的定量限为2μg/kg,嘧菌酯和吡唑醚菌酯的定量限为4μg/kg,Z-苯氧菌胺和醚菌酯的定量限为10 μg/kg.各杀菌剂的回收率为60.4％ ～ 110％,相对标准偏差为1.2％～17％.该方法能满足麦冬、玄参、延胡索中7种目标杀菌剂残留量的检测.%An LC-MS/MS method was developed for the simultaneously determination of seven strobilurin fungicide residues in Chinese herbs. The strobilurin fungicides include Z-metominos-trobin, kresoxim-methyl, dimoxystrobin, picoxystrobin, pyraclostrobin, azoxystrobin and tri-floxystrobin. The sample was extracted with ethyl acetate and cleaned-up by an amino SPE column. The seven strobilurin fungicide residues were separated on a C18 column with gradient elution of 1.0‰ formic acid and methanol as mobile phases, and detected by ESI-MS in positive ion and selective reaction monitoring (SRM) mode. External standard method was used to the quantification with good linear relationships (r≥0.996). The LOQs were 2 μg/kg for dimoxystrobin, picoxystrobin and trifloxystrobin, 4 μg/kg for pyraclostrobin and azoxystrobin, 10 μg/kg for Z-metominostrobin and kresoxim-methyl. The recoveries were from 60.4% to 110% with the RSDs between 1.2% and 17%. The developed method is suitable for the determination and confirmation of the seven strobilurin fungicide residues in the three of Eight Zhes ( Ophiopogon japoni-cus (Thunb. ), Scrophularia ningpoensis Hemsl. and Corydalis yanhusuo W T Wang).
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