测定鱼腥草中百草枯和乙草胺残留的三重四级杆气相色谱质谱法

试验建立了测定鱼腥草中百草枯和乙草胺残留物的三重四级杆气相色谱质谱方法。样品采用高速匀浆提取,固相萃取(SPE)净化,(GC-MS/MS)检测,在0.02～0.50 mg/L范围内,目标物的峰面积与其质量浓度的线性关系良好(R2>0.99);在0.02、0.10、0.50 mg/kg添加水平,样品添加平均回收率为73.5%～81.2%,相对标准偏差(RSD,n=6)为3.43%～4.49%。乙草胺检出限为0.00020mg/kg,定量限为0.0008mg/kg;百草枯检出限为0.001 4 mg/kg,定量限为0.005 0 mg/kg。该方法具有灵敏、快速、准确、线性范围宽等优点,适用于鱼腥草中农药残留检测。

Determination of Paraquat and Acetochlor Residues in Houttuynia Cordata by Gas Chromatog- raphy-quadrupole Mass Spectrometry

A triple quadrupole gas chromatography mass spectrometry method was developed for the determina- tion of paraquat and acetochlor residues in Houttuynia cordata in the current work. The sample were extraced using high-speed homogenate, and then purified by solid phase extraetion （SPE） determined by GC-MS/MS. The linear relation between peak area and mass eoncentration of sample were good from 0. 02 mg/L to 0. 50 mg/L（R2 〉0.99）. The average recovery rate were 73.5% -81.2% of target compounds and the relative standard deviation （RSD, n = 6） were from 3.43% to 4.49% in three spiked levels at 0.02 mg/kg, 0.10 mg/kg and 0.50 mg/kg. The limit of detection quantification of acetochlor was 0. 000 2 mg/kg and limit of quantification 0. 000 8 mg/kg. The limit of detection quantification of paraquat was 0. 0014 mg/kg and limit of quantification 0. 0050 mg/kg. The method is sensitive, rapid, precise, and widely linear, therefore it is suit- able for the determination of Houttuynia cordata pesticide residues.