以氣相層析儀附電子捕獲檢測器分析甘蔗中得拉本殘留量   全文下載

Determination of Residual Dalapon in Sugarcane by Gas Chromatograph Equipped with Electron Capture Detector (GC-ECD)

本研究建立了以酸性甲醇（acidic methanol）進行衍生化及以氣相層析儀附電子捕獲檢測器分析甘蔗中得拉本（dalapon）殘留量之分析方法。均質後之作物檢體，以硫酸水溶液萃取出檢體中之得拉本，加入食鹽以增加離子強度後再以乙醚進行振盪萃取，以10%硫酸甲醇溶液（10% H2SO4 methanolic solution）進行酯化，最後以氣相層析附電子捕獲檢測器進行檢測。添加得拉本0.05~0.20 ppm於甘蔗中，平均回收率為89.7~109.4%，變異係數為1.0~9.3%，最低檢出限量可達0.01 ppm。甲酯得拉本波峰以氣相層析質譜圖作進一步定性確認。此分析法之流程簡便，且使用之試劑毒性低，適合作物中得拉本殘留量之精確定量分析。

A gas chromatographic method using an electron capture detector (GC-ECD) was developed for the determination of residual dalapon, esterified with methanol in sulfuric acid, in sugarcane. Dalapon in plant matrix was initially extracted with sulfuric acid solution, followed by partition extraction with diethyl ether in the presence of NaCl and esterification with 10% H2SO4 methanolic for GC-ECD analysis. Recovery of dalapon (0.05~0.20 ppm) spiked in sugarcane samples was carried out to obtain an average recovery of 89.7~109.4% with a coefficient of variation (CV) of 1.0~9.3% and a method detection limit (MDL) of 0.01 ppm. Peak of dalapon methyl ester was further identified by a GC-MS spectrum. The developed procedure was simple and the reagents used were slightly toxic, thus suitable for the accurate quantification of dalapon residues in crops. 本研究建立了以酸性甲醇（acidic methanol）進行衍生化及以氣相層析儀附電子捕獲檢測器分析甘蔗中得拉本（dalapon）殘留量之分析方法。均質後之作物檢體，以硫酸水溶液萃取出檢體中之得拉本，加入食鹽以增加離子強度後再以乙醚進行振盪萃取，以10%硫酸甲醇溶液（10% H2SO4 methanolic solution）進行酯化，最後以氣相層析附電子捕獲檢測器進行檢測。添加得拉本0.05～0.20 ppm於甘蔗中，平均回收率為89.7～109.4%，變異係數為1.0～9.3%，最低檢出限量可達0.01 ppm。甲酯得拉本波峰以氣相層析質譜圖作進一步定性確認。此分析法之流程簡便，且使用之試劑毒性低，適合作物中得拉本殘留量之精確定量分析。