應用多孔性矽藻土管柱於蔬菜及米中丁基拉草及賓克隆殘留量之分析   全文下載

Determination of Butachlor and Pencycuron Residues in Vegetables and Rice: Application of the Macroporous Diatomaceous Earth Column

丁基拉草（butachlor）及賓克隆（pencycuron）分別係國內常用之殺草劑及殺菌劑，此兩種農藥於農產品中之殘留量並無公告之檢驗方法，本研究建立了應用多孔性矽藻土管柱（Macroporous Diatomaceous Earth Colunm； MDE colunm）及矽酸鎂固相萃取匣（florisil cartridge for solid phase extraction； ）進行檢體之淨化以檢測農產品中丁基拉草（butachlor）及賓克隆（pencycuron）殘留量之方法。本檢驗係以丙酮為抽出溶媒，濃縮液通入多孔性矽藻土管柱，以正己烷沖提，再經矽酸鎂固相萃取匣淨化，先以5%乙醚之正己烷溶液（diethyl ether／n-hexane； E／H） 沖洗，續以15%E／H及15%乙酸乙酯之正己烷溶液（ethyl acetate／hexane； EA／H）沖提，分別收集15% E／H沖提液（I）及15% EA／H沖提液（II），沖提液（I）以氣相層析儀附電子捕獲檢出器（GC-ECD）偵測丁基拉草，沖提液（II）以高效液相層析儀附紫外光檢出器（HPLC-UV）於波長248nm偵測賓克隆。添加丁基拉草及賓克隆各0.25~0_75 ppm於米及小白菜中，丁基拉草之回收率為84.9~94.9%，賓克隆之回收率為88.3~94.8%。本檢驗方法之最低檢出限量兩者皆為0.05 ppm。利用多孔性矽藻土管柱取代傳統之液、液分配萃取，及以矽酸鎂固相萃取匣進行檢體之淨化來檢測農產品中丁基拉草及賓克隆殘留量，回收率佳、再現性良好且操作簡易、快速，並具足夠之靈敏度，可作為相關單位訂定標準檢驗方法之依據，並進一步評估應用於農產品中農藥多重殘留之檢測。

Butachlor and pencycuron are commonly used pesticides in Taiwan, but still lack official methods for determining butachlor and pencycuron residues in agricultural products. An analytical method using a macroporous diatomaceous earth (MDE) column and florisil cartridge for cleanup procedure was developed for determination of butachlor and pencycuron in vegetables and rice. Butachlor and pencycuron were extracted from crops with acetone and the concentrated extract was transferred into the MDE column, eluted with n-hexane. The eluate was concentrated and applied on a florisil cartridge. The cartridge was washed with 5% diethyl ether in n-hexane (E/H), and then eluted with 15% E/H (fraction I) and 15% ethyl acetate in n-hexane (EA/H) (fraction II). Butachlor residue in fraction I was determined by GC-ECD. Pencycuron residue in fraction II was determined by HPLC-UV at 248 nm. Chinese mustard and rice samples were fortified with butachlor and pencycuron at levels of 0.25~0.75 ppm and analyzed. The recoveries of butachlor and pencycuron were between 84.9~94.9% and 88.3~94.8%, respectively. The detection limits of both pesticides in Chinese mustard and rice were 0.05 ppm. MDE liquid/liquid extraction cartridges provide a means of simplifying and speeding up multiple liquid/liquid extractions. 丁基拉草（butachlor）及賓克隆（pencycuron）分別係國內常用之殺草劑及殺菌劑，此兩種農藥於農產品中之殘留量並無公告之檢驗方法，本研究建立了應用多孔性矽藻土管柱（Macroporous Diatomaceous Earth Colunm； MDE colunm）及矽酸鎂固相萃取匣（florisil cartridge for solid phase extraction； ）進行檢體之淨化以檢測農產品中丁基拉草（butachlor）及賓克隆（pencycuron）殘留量之方法。本檢驗係以丙酮為抽出溶媒，濃縮液通入多孔性矽藻土管柱，以正己烷沖提，再經矽酸鎂固相萃取匣淨化，先以5%乙醚之正己烷溶液（diethyl ether／n-hexane； E／H） 沖洗，續以15%E／H及15%乙酸乙酯之正己烷溶液（ethyl acetate／hexane； EA／H）沖提，分別收集15% E／H沖提液（I）及15% EA／H沖提液（II），沖提液（I）以氣相層析儀附電子捕獲檢出器（GC-ECD）偵測丁基拉草，沖提液（II）以高效液相層析儀附紫外光檢出器（HPLC-UV）於波長248nm偵測賓克隆。添加丁基拉草及賓克隆各0.25～0_75 ppm於米及小白菜中，丁基拉草之回收率為84.9～94.9%，賓克隆之回收率為88.3～94.8%。本檢驗方法之最低檢出限量兩者皆為0.05 ppm。利用多孔性矽藻土管柱取代傳統之液、液分配萃取，及以矽酸鎂固相萃取匣進行檢體之淨化來檢測農產品中丁基拉草及賓克隆殘留量，回收率佳、再現性良好且操作簡易、快速，並具足夠之靈敏度，可作為相關單位訂定標準檢驗方法之依據，並進一步評估應用於農產品中農藥多重殘留之檢測。