以5-(4,6-三氯-s-三嗪基-2-氨基)荧光素为衍生试剂,建立了一种微乳电动色谱-激光诱导荧光检测法分析麻黄碱和伪麻黄碱的新方法。经过实验条件的优化,使用50mmol/L硼砂,5%微乳液(V/V)(微乳液组成(W/W)3.24%正己烷,3.24%SDS,26.44%正丁醇,57.08%水),14%乙腈(V/V)作为运行缓冲溶液,电压22.5kV,温度为25℃条件下,11min内可实现基线分离。分析物的峰高与浓度(2.5-75μg/L)之间存在较好的线性关系,相关系数为0.9915(麻黄碱)和0.9981(伪麻黄碱);检出限分别为2.39×10^-3和3.85×10^-3μg/L。将该法成功用于麻黄及其制剂中两种生物碱的分析,回收率在92.0%-108.4%之间。
A rapid microemulsion electrokinetic chromatography (MEEKC) with laser-induced fluorescence (LIF) detection method for the analysis of ephedrine (E) and pseudoephedrine (PE) after derivatizated by 5- (4,6-dichloro-s-triazin-2-ylamino) fluorescein (DTAF) was proposed. After a series of optimization, the baseline separation of the two alkaloids could be obtained in less than 11 min with a running buffer consisting of 50 mmol/L borate sodium, 5% (WV) microemulsion (n-heptane (3.24%, W/W), SDS (3.24%, W/W), n-butanol (26.44%, W/W) and distilled water (57.08%, W/W), 14% acetonitrile, and a voltage of 22.5 kV, a temperature of 25 ℃. A linear relationship for E and PE was obtained in the range of 2.5 - 75 μg/L (correlation coefficients: 0. 9915 for E and 0. 9981 for PE), and the detection limits for E and PE were 2.39 × 10^-3 μg/L, 1.09 × 10 -3 μg/L, respectively. The proposed method was applied to the analysis of the two alkaloids in ehpedra herb and its preparations with recoveries in the range of 92.0% -108.4%.