Jing Haoran, Guo Huaizhong, Wang Zijun, Wang Min, Zhang Bin
Hebei Key Laboratory of Drug Quality Research, School of Pharmacy, Hebei University, Baoding 071002, China.
Zhongguo Zhong Yao Za Zhi. 2009 Apr;34(8):980-3.
To establish a method for the determination of ephedrine and pseudoephedrine in Herba Ephedrae and Maxing Shigan Tang by capillary zone electrophoresis.
The conditions of the experiment were optimized with a fused-silica capillary of 60 cm x 50 microm (50 cm effective length) in a running buffer of 50 mmol x L(-1) borax-20 mmol x L(-1) threonine (pH 9.27) and an applied voltage of 15 kV (room temperature). Samples were introduced by hydrodynamic injections (10 cm x 20 s)and determined with on-column UV monitoring at 210 nm. Phenobarbital was chosen as the internal standard.
Ephedrine and pseudoephedrine are separated successfully within 8 min. The linear responses covered the ranges from 21.3 to 213 mg x L(-1) (r = 0.9996) for ephedrine and from 8.4 to 84 mg x L(-1) (r = 0.9995) for pseudoephedrine. The detection limits (S/N = 3) of ephedrine and pseudoephedrine were shown to be 1.45 and 1.48 microg x mL(-1), respectively, The quantitation limits (S/N = 10) of ephedrine and pseudoephedrine were shown to be 4.81 and 4.93 mg x L(-1), respectively. The average recoveries for ephedrine and pseudoephedrine were 97.5% and 98.6% with RSD less than 5.0%.
The method is simple, rapid, cost-effective and precise with satisfactory results.
建立毛细管区带电泳法测定麻黄及麻杏石甘汤中麻黄碱和伪麻黄碱的方法。
采用60 cm×50 μm(有效长度50 cm)的熔融石英毛细管,以50 mmol·L⁻¹硼砂 - 20 mmol·L⁻¹苏氨酸(pH 9.27)为运行缓冲液,在15 kV(室温)的施加电压下优化实验条件。通过流体动力学进样(10 cm×20 s)引入样品,并在210 nm处进行柱上紫外监测测定。选用苯巴比妥作为内标。
麻黄碱和伪麻黄碱在8分钟内成功分离。麻黄碱的线性响应范围为21.3至213 mg·L⁻¹(r = 0.9996),伪麻黄碱的线性响应范围为8.4至84 mg·L⁻¹(r = 0.9995)。麻黄碱和伪麻黄碱的检测限(S/N = 3)分别为1.45和1.48 μg·mL⁻¹,定量限(S/N = 10)分别为4.81和4.93 mg·L⁻¹。麻黄碱和伪麻黄碱的平均回收率分别为97.5%和98.6%,相对标准偏差小于5.0%。
该方法简便、快速、经济高效且准确,结果令人满意。