本研究以微胞電動力毛細管層析法（micellar electrokinetic chromatography, MEKC）結合紫外可見光吸收偵測器（UV-Vis absorbance detection, UV）開發快速分離與偵測五種農藥：亞滅培（acetamiprid）、達滅芬（dimethomorph）、芬普蟎（fenpyroximate）、覆滅蟎（formetanate）和滅達樂（metalaxyl）的分析方 法。本研究探討偵測波長、聚山梨醇酯20（polyoxyethylene sorbitan monolaurate, Tween 20） 和十六烷基三甲基溴化銨（hexadecyltrimethylammonium bromide, CTAB）的濃度、pH 值、磷酸鹽緩衝溶液濃度對分離的影響。最佳化的分離條件 為5.0 mM 磷酸緩衝溶液（pH 8.0）含有0.2% Tween 20 與20 mM CTAB，偵測器 波長設定於228 nm、電壓-12.5 kV 下進行毛細管電泳分析，可在16 分鐘內達到 基線分離。此方法最低偵測極限（limit of detection, LOD）在訊號／雜訊比（S/ N ratio）等於3 可達0.027 ppm（亞滅培），最高為0.235 ppm（滅達樂），五種分 析物的線性相關係數（R2）值皆大於0.986。最後，將杭菊樣品依照歐盟現行的 QuEChERS 方法進行樣品前處理，並分別添加三種不同濃度的覆滅蟎、亞滅培、 滅達樂，可以成功偵測並且定量，回收率介於85% ～ 115% 之間。

In this study, we developed an analytical method for determination of five pesticides (acetamiprid, dimethomorph, fenpyroximate, formetanate, and metalaxyl) using micellar electrokinetic chromatography coupled with UV detection (MEKC-UV). The optimal separation conditions for MEKC-UV were using a 5.0 mM phosphate buffer (pH 8.0) containing 0.2% polyoxyethylene sorbitan monolaurate (Tween 20) and 20 mM hexadecyltrimethylammonium bromide (CTAB). UV detector was set at 228 nm, and the applied voltage is -12.5 kV. Under these conditions, the pesticides were separated in 16 min and the detection limit (S/N = 3) of formetanate, acetamiprid, metalaxyl, dimethomorph, fenpyroximate were 0.35, 0.12, 0.84, 0.15, and 0.41 μM, respectively. The linear ranges of the five pesticides were from 3 μM to 30 μM for formetanate、1 μM to 30 μM for acetamiprid and dimethomorph、3 μM to 40 μM for metalaxyl、3 μM to 50 μM for fenpyroximate, with all R2 larger than 0.986. This method was successfully applied to analyze the pesticides in chrysanthemum powder sample. The results revealed that the recovery of three pesticides in chrysanthemum powder were 85% ～ 115%.