【摘要】 研究建立了高含量基体干扰大葱样品中有机磷农药残留量分析方法。采用乙腈水提取,有机相盐析后经硅胶柱净化,以双毛细柱GC-FPD定性定量,该方法对8种有机磷农药的添加回收率为60%~130%,RSD<18%,检出限为0.02~0.05 mg.kg-1,符合残留分析要求。更多还原

【Abstract】 Gas chromatography hyphenated with solid-phase extraction was applied to the rapid determination of 8 residual organophosphorus pesticides（Opp′s） in welsh onion.The onion sample（25 g） was extracted with a mixture containing 50 mL of acetonitrile and 10 mL of sat′d NaCl water solution.The extract was filtered and salted out with 6 g of NaCl by shaking vigorously for 3 min in a separatory funnel.10.0 mL of the organic phase was evaporated（at 40 ℃） to dryness,and the residue was taken up with 1.0 mL of nhexane,and purified by SPE on silica gel column（Accu Bond Ⅱ silica cartridges）.The Opp′s on the column was eluted with acetone-n-hexane（（1+1）） mixture and 15 mL of the eluate was taken and dried by blowing with nitrogen.n-Hexane（1.0 mL） was used to dissolved the residue and the solution was used for GC determination.Two capillary columns（HP 5 and DB1701） with different polarity were used in the GC identification and determination,and two flame photometric detectors were used.Recoveries for the 8 Opp′s were tested by the standard addition method and the results obtained were in the range of 60%-130%.RSD′s found were less than 18%.Detection limits were in the range of 0.02-0.05 mg·kg^-1.更多还原