吡草醚在棉花及土壤中的残留分析方法研究

研究建立了吡草醚在棉花及土壤中的残留分析方法。棉叶和棉籽样品以乙腈提取，GCB/PSA固相萃取小柱净化，高效液相色谱测定。土壤样品以丙酮提取，C₁₈小柱净化。吡草醚在棉叶、棉籽和土壤中的最低检测浓度均为0.02 mg·kg^-1。吡草醚在棉叶、棉籽和土壤中的平均添加回收率（添加浓度为0.02~1 mg·kg^-1）分别为93.94%~101.65%、84.88%~98.62% 和85.49%~90.71%，变异系数分别为3.96%~8.06%、7.59%~10.37% 和5.59%~ 8.69%。方法的准确性、精确性和灵敏度均达到农药残留分析的要求。

An analytical method for determination of pyraflufen-ethyl residues in the cotton plant and soil

High performance liquid chromatography (HPLC) was used to analyze pyraflufen-ethyl residues in the cotton plant and soil. Pyraflufen-ethyl residues were extracted from leaves and cottonseeds with acetonitrile and purified using GCB/PSA SPE microcolumn. The residues were determined using HPLC equipped by PDA. Pyraflufen-ethyl residues in the soil were extracted with acetone and purified using C₁₈ SPE microcolumn. The minimum detectable concentration of pyraflufen-ethyl in the cotton leaf, cottonseed, and the soil was 0.02 mg·kg^-1. The average recoveries of pyraflufen-ethyl in the cotton leaf, cottonseed, and the soil were 93.94%-101.65%, 84.88%-98.62%, and 85.49%-90.71%, respectively, and their variation coefficients were 3.96%-8.06%, 7.59%-10.37% and 5.59%-8.69%, respectively. The results showed that this method met all criteria for the pesticide residue analysis.