微細胞電動層析法同時測定乳品中三聚氰胺及其衍生物   全文下載

Simultaneous Determination of Melamine, Ammelide, Ammeline and Cyanuric Acid in Milk Products by Micellar Electrokinetic Chromatography

本研究以微細胞電動層析法（MEKC）使用塗有陽離子聚合物（poly (diallyldimethylammonium chloride)）的熔矽管柱，同時測定三聚氰胺（melamine）、三聚氰酸二醯胺（ammeline）、三聚氰酸一醯胺（ammelide）和三聚氰酸（cyanuric acid）。pH 值 9.15 之 5 mM 硼酸，5 mM 四硼化鈉， 10 mM 十二烷基硫酸鈉及 2 mM 四丁基氫氧化銨為背景電解質，電壓 20 kV和波長 210 nm 時進行分離，4 種化合物在 5.2 分鐘內完全分離。melamine、 ammeline、ammelide 和 cyanuric acid 的偵測極限分別為 0.10、0.04、0.03 和0.08 μg/mL。melamine、ammeline、ammelide 和 cyanuric acid 的滯留時間相對標準偏差分別為 0.14，0.29，0.05 和 0.12%，峰面積分別為 0.11，0.36，0.28和 0.24%。本方法已成功地應用於檢測牛奶中的三聚氰胺及其衍生物。分析之前，需以鹽酸去除牛奶檢體中蛋白質，並以 Sep-Pak C18 管柱淨化剩餘的基質，否則會造成電泳的去堆疊化。結果顯示，保久乳檢體中含三聚氰胺和三聚氰酸。

Micellar electrokinetic chromatography (MEKC) was developed for the simultaneous determination of melamine, ammeline, amme-lide and cyanuric acid on a fused silica column coated with poly (diallyldimethylammonium chloride). Separation was performed using 5 mM boric acid, 5 mM sodium tetraborate, 10 mM sodium dodecylsulfate and 2 mM tetrabutylammonium hydroxide at pH 9.15 as the background electrolyte, an applied voltage of +20 kV and UV detection at 210 nm. The four compounds were completely separated within 5.2 min. The detection limits of melamine, ammeline, ammelide and cyanuric acid were 0.10, 0.04, 0.03 and 0.08 µg/mL, respectively. The relative standard deviations of retention times for melamine, ammeline, ammelide and cyanuric acid were 0.14, 0.29, 0.05 and 0.12%, and those of peak areas were 0.11, 0.36, 0.28 and 0.24%, respectively. The method was successfully applied to determine melamine and its derivative in milk samples. Before analysis, protein in milk sample was removed using HCl and the remaining matrix was cleaned up using Sep-Pak C18, which otherwise caused electrophoretic de-stacking. The results showed that melamine and cyanuric acid were found in UHT milk samples.