臺灣博碩士論文加值系統

苯氧酸系除草劑為有機氯農藥的一種，由於其羧酸之特性，易形成離子態，透過地表流逕或土壤淋洗作用而傳輸到地下水，進一步威脅飲用水安全。本研究開發對環境水樣品中的苯氧酸系除草劑綠色檢測法。
將純水加熱至超過沸點後施加足夠壓力使其保持在液態，即稱之為次臨界水。其極性及介電常數隨溫度上升而下降，而與有機溶劑有相似的性質，因此可用於取代傳統HPLC的有機沖提液。本研究使用水溶液為動相，以 Hamilton PRP-1管柱對苯氧酸系除草劑做分離，因分析物帶有強極性的酸根，只使用純水作為動相分離效果並不理想，因此本實驗在動相中添加離子對試劑CH3NH3+，吸附在靜相上的CH3NH3+與分析物之酸根結合後，可增加分析物在管柱中的滯留效果。此種以離子對方式於分離管柱中分離陰離子的方法稱為離子對層析法 ( Ion-pair Chromatography )。
研究中利用微透析萃取結合次臨界水離子對層析法分析水樣中苯氧酸系除草劑，檢測對象包括2,4-D、MCPP、2,4,5-T。取15cm之醋酸纖維透析膜，灌流萃取液使用正辛醇，對30 mL水樣品（調整至pH 2），在400 rpm磁石攪拌下靜態萃取30 min後，以1μL/min的流速進樣17分鐘，將萃取液直接連線推入進樣閥，再以次臨界水離子對層析系統分析。以本方法最佳條件分析2,4-D、MCPP及2,4,5-T，其線性範圍在10- 500 μg/L，其相關係數在0.9960-0.9992之間。偵測極限分別為2 μg/L（2,4-D）、4 μg/L（MCPP）、6 μg/L（2,4,5-T）。所發展之檢測技術，應用於農田溝渠水樣品，偵測到含有15 μg/L 的2,4-D、7 μg/L 的MCPP、9 μg/L的2,4,5-T殘留，回收率介於70-85％。

In this study, we have developed a novel green route analytical method for the determination of phenoxy acid herbicides (2,4-D, 2,4,5-T, and MCPP) in water sample using on-line microdialysis extraction coupled with subcritical water ion-pair chromatography.
Microdialysis extraction liquid (1-Octanol) and Cellulose Acetate dialysis membrane were employed to extract the analytes from the agricultural water in Yunlin city, Taiwan. The Cellulose Acetate dialysis membrane was directly connected to the injection valve of subcritical water ion-pair chromatography system. After the microdialysis extraction, the extracted analytes were on-line introduced into the subcritical water separation column (Hamilton PRP-1) and detected by a UV detector.
Under the optimal microdialysis extraction and subcritical water ion-pair chromatography conditions, the linear range for 2,4-D, MCPP and 2,4,5-T were 10–500 μg/L. The correlation coefficients were between 0.9960-0.9992. The limit of detection were 2 μg/L for 2,4-D, 4 μg/L for MCPP and 6 μg/L for 2,4,5-T. The recoveries of phenoxy acid herbicides in real sample (agricultural water) were between 70-85%.
This method was using no organic solvent and could achieve good separation. The limits of detection were acceptable. So the proposed method provides a simple and eco-friendly procedure for isolating and determining phenoxy acid herbicides in agricultural water.

摘 要 i
Abstract ii
目 錄 iii
表 目 錄 v
圖 目 錄 vi
第一章　緒論 1
ㄧ、　研究緣起 1
二、　苯氧酸系除草劑之簡介 1
三、　苯氧酸系除草劑分析樣品前處理技術 3
(一)　液相-液相萃取法（Liquid-Liquid extraction，LLE） 3
(二)　固相萃取法（Solid Phase Extraction，SPE） 4
(三)　固相微萃取（Solid Phase Microextraction，SPME） 4
(四)　微透析技術 ( Microdialysis ) 9
四、　次臨界水 (subcritical water)概述 14
(一)　特性簡介 14
(二)　文獻回顧─次臨界水層析法 19
(三)　離子對層析法 ( Ion-pair Chromatography ) 24
第二章　實驗材料與研究方法 26
一、　藥品、器材、儀器設備 26
(一)　藥品 26
(二)　器材 26
(三)　儀器設備 27
(四)　儀器裝置圖 28
二、　藥品配製 29
(一)　動相的配製 29
(二)　苯氧酸系除草劑標準品100 mg/L混合儲存溶液之配製 29
(三)　直接注入法苯氧酸系除草劑檢量線範圍濃度溶液之配製 29
(四)　經微透析苯氧酸系除草劑檢量線範圍濃度溶液之配製 29
(五)　真實樣品 29
三、　儀器設計及操作條件 30
(一)　高效能液相層析儀系統 30
(二)　微透析系統 30
(三)　次臨界水層析系統的建構 31
(四)　微透析萃取最佳化條件之探討 33
(五)　再現性探討及真實樣品測定 34
第三章 結果與討論 36
ㄧ、　次臨界水層析法最佳化條件之探討 36
(一)　離子對試劑添加量之探討 36
(二)　動相pH值之探討 39
(三)　烘箱溫度探討 39
(四)　LC幫浦流速探討 39
(五)　次臨界水層析系統最佳化條件 42
二、　微透析萃取最佳化條件之探討 44
(一)　灌注萃取液選擇 44
(二)　靜態萃取時間 44
(三)　微量幫浦流速 44
(四)　磁石攪拌速度 47
(五)　微透析萃取最佳化參數 47
三、　再現性探討 51
(一)　苯氧酸系除草劑直接注入次臨界水層析再現性探討 51
(二)　 苯氧酸系除草劑經微透析注入次臨界水層析法再現性探討 51
四、　校正曲線的建立及偵測極限測定 52
五、　真實樣品分析 55
(一)　直接檢測 55
(二)　以添加方式檢測 55
第四章　結論 59
第五章　文獻參考 60

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