分散固相萃取-超高效液相色谱-串联质谱联用快速检测大豆及土壤中氟磺胺草醚残留

采用分散固相萃取(QuEChERS)样品前处理方法,建立了超高效液相色谱-串联质谱(UPLC-MS/MS)快速检测大豆和土壤中氟磺胺草醚的残留分析方法.大豆和土壤样品采用乙腈(含0.5%甲酸)提取,N-丙基乙二胺(PSA)或石墨化碳黑(GCB)净化,UPLC-MS/MS外标法检测定量.在0.005—0.5 mg.kg-1添加范围内,氟磺胺草醚在土壤、大豆和大豆植株中的平均回收率在79.4%—109.0%之间,变异系数在3.6%—10.1%之间.在山东、河南、吉林进行了氟磺胺草醚在大豆植株和土壤中的降解动态研究,结果表明,试验点中氟磺胺草醚在土壤中的降解半衰期为8.5—23.7 d;在大豆植株中的降解半衰期为2.7—9.8 d.

Determination of fomesafen residues in soybean and soil using Quechers and UPLC-MS/MS

A rapid method for the determination of fomesafen residues in soybean and soil was established based on QuEChERS and ultraperformance liquid chromatography-mass spectrometry(UPLC-MS/MS).The sample was extracted by acetonitrile(containing 0.5% formic acid) and then purified by primary secondary amine(PSA) or graphitized carbon black(GCB).The fomesafen residues was analyzed by UPLC-MS/MS under multiple reaction monitoring mode and quantified with external standards.Average recoveries of fomesafen in soil,soybean,soybean plant at three levels(0.005 mg · kg-1,0.05 mg · kg-1 and 0.5 mg · kg-1) ranged from 79.4% to 109.0% with relative standard deviations from 3.6% to 10.1%.This method was used to determine fomesafen residues in soil and soybean plant samples for the studies on their dissipation under field conditions.The results showed that the half-lives of fomesafen ranged from 8.5 to 23.7 days in soil and from 2.7 to 9.8 days in soybean plant in Shandong,Henan and Jilin,respectively.