气相色谱/原子发射检测法测定毒死蜱中的杂质

 利用气相色谱 /原子发射检测 (GC/AED)法 ,并通过元素内标测定 ,对农药毒死蜱产品分别进行碳 (4 96nm和193nm)、氯 (4 79nm)和硫 (181nm)等通道的选择性定量检测。根据检测结果及由气相色谱 /质谱 (GC/MS)测得的分子结构式 ,分别计算杂质的质量分数。由此可知 ,各组分从不同通道得到的定量结果比较接近 ,对杂质的最大相对误差不超过 5 8%。在无纯物质作标样的条件下 ,该方法比气相色谱 /火焰离子化检测 (GC/FID)面积归一化法更为可靠 ,可作为对农药及其他复杂有机混合物准确、方便的定量方法。

Determination of Impurities in a Technical Chlorpyrifos by Gas Chromatography with Atomic Emission Detection

Mass fraction of impurities in a technical chlorpyrifos sample may be obtained by selective determination on carbon (496 nm and 193 nm),chlorine(479 nm),and sulfur(181 nm) channels using gas chromatography with atomic emission detection(GC/AED) According to the formulas from GC/MS and analytical results from GC/AED, mass fraction of compounds may be calculated by internal standard of elements The results for the same compound obtained from different elemental channels were consistent This shows the responses of carbon, chlorine and sulfur on AED are independent on molecular structures Moreover, the reliability of the qualitative results of impurities from GC/MS was proved If the formulas from GC/MS were wrong, the results from different elemental channels on GC/AED would be different The relative deviations were in the range of -3 4% to 5 8% When standards are not available, the results from GC/AED are more reliable than those from GC/FID which usually depend on the area normalization without corrections Pesticides and other complex organic mixtures may be analyzed reliably and expediently by this method