固相萃取—气相色谱法测定大豆粉中的有机磷

建立了一种快速测定大豆粉中有机磷农药残留的气相色谱法。试样中的农药残留用乙腈提取,提取液经氮气浓缩后用C18柱和Envi-Carb＋NH2串联柱净化,气相色谱—火焰光度检测器（FPD）测定。有机磷农药的加标回收率为92.6-105%,在0.1-4mg/kg内有比较好的线性关系,相关系数为0.999,方法的检出限为0.005mg/kg。该方法灵敏度、准确度和精密度均符合农药残留测定的技术要求。

Determination of organophosphorus pesticide residues in soybean flour by solid phase extraction-gas chromatography

A rapid and sensitive method has been established for the determination of organophosphorus pesticide residues in soybean flour. The pesticide residues in soybean flour samples were extracted with acetonitrile, the extracts were concentrated with stream of nitrogen, cleaned up by C18 column and Envi- Carb ＋NH2 SPE cartridges, and then determined by gas chromatography with flame photometric detector （FPI））. The mean recoveries of organophosphorus pesticide residues in soybean flour ranged from 92.6% to 105%. When the mass concentrations ranged from 0.1 mg/kg to 4 mg/kg, the linearities were found to be in the correlation coefficient of 0.999 for the tested pesticides between the mass concentrations and peak areas. The detection limit of this method was 0.005 mg/kg. The proposed method is characterized by simplicity, higher sensitivity and accuracy.