QuEChERS-气相色谱-质谱法测定大米中的10种酰胺类除草剂残留量

Simultaneous determination of 10 kinds of amide herbicide residues in rice by QuEChERS with gas chromatography-mass spectrometry

中文关键词:  气相色谱-质谱法  QuEChERS方法  酰胺类除草剂  大米

英文关键词:gas chromatography-mass spectrometry  QuEChERS method  amide herbicides  rice

中文摘要:

      目的 建立一种QuEChERS结合气相色谱-质谱法同时测定大米中10种酰胺类除草剂农药(甲草胺、乙草胺、丙草胺、丁草胺、异丙甲草胺、氟酰胺、二甲戊乐灵、灭锈胺、吡氟酰草胺和苯噻酰草胺)残留的分析方法。方法 样品经乙腈提取, QuEChERS方法净化浓缩后, 以气相色谱-质谱法采用选择离子监测模式进行分析, 用灵敏度最高的离子对定量。结果 在0.05~0.5 mg/L范围内, 10种除草剂农药线性关系良好, 线性相关系数(r2)不小于0.99, 方法检出限均小于9 μg/kg。在0.05、0.2和0.5 mg/L 3个添加水平下, 平均加标回收率为82.9%~107.9%, 相对标准偏差为1.2%~5.7% (n=6)。结论 该法具有前处理快速简单、精密度好、灵敏度高等优点, 适用于大米中酰胺类除草剂农残的快速验证和定量检验。

英文摘要:

      Objective To establish a method for the simultaneous determination of 10 kinds of amide herbicide residues (alachlor, acetochlor, pretilachlor, butachlor, metolachlor, flutolanil, pendimethalin, mepronil, diflufenican and mefenacet ) in rice by QuEChERS pretreatment with gas chromatography-mass spectrometry (GC-MS). Methods The sample was extracted with acetonitrile, purified and concentrated by QuEChERS method, and analyzed by GC-MS using selective ion monitoring mode, and quantified by the most sensitive ion pair. Results In the range of 0.05-0.5 mg/L, 10 kinds of herbicides had good linear relationships, the linear correlation coefficients (r2) were not less than 0.99, and the detection limits of the method were less than 9 μg/kg. At the 3 spikes of 0.05, 0.2 and 0.5 mg/L, the average recoveries were 82.9%-107.9%, and the relative standard deviations were 1.2%-5.7% (n=6). Conclusion The method has the advantages of quick and simple pretreatment, high precision and high sensitivity, which is suitable for rapid verification and quantitative inspection of amide herbicide residues in rice.