高效毛细管电泳安培法测定麦冬中薯蓣皂甙元的含量

Determination of Diosgenin in Radix Ophiopogonis with Amperometric Detection by Capillary Electrophoresis

建立了麦冬中薯蓣皂甙元含量的高效毛细管电泳安培检测方法。着重探讨了缓冲溶液种类、浓度、酸碱度，工作电位，有机改性剂及其操作电压、进样时间等对检测的影响。Na2B4O7-NaOH（Na2B4O7浓度为30mmol·L^-1）为缓冲液，工作电位为0．4V，φ为7％甲醇为有机添加剂，进样时间为5s，在15kV分离高压，pH=9．5的碱性条件下柱端安培法检测了薯蓣皂甙元的含量。该法的线性范围为：100～1mg·L^-1，线性方程为y=17224＋8722c，相关系数r=0．9995，检出限为0．1mg·L^-1。

Abstract： Diosgenin in radix ophiopogonis was determined by capillary electrophoresis with amperomet-ric detection （CE-AD）. The affected conditions, such as the running buffer pH value （pH）, the types of running buffer, the concentration of running buffer, the detection potential, the applied voltage and the sampling time were investigated. The optimized condition was in a running buffer composed of 30 mmol/ L Na2B4O7 buffer at a pH 9.5, separation voltage at 15 kV, injection time for 5 s, organic additive for 7% methanol and detection potential at 0.4 V. A linear relation between peak area （Y） and mass concentration of diosgenin （c） was obtained in the range of 1 -100mg · L^-1 （r = 0. 999 5） and the determination limit is 0. 1 mg · L^-1.