毛细管电泳分离与测定大鼠血浆中尼群地平和尼莫地平对映体的浓度

Chiral separation and determination of nitrendipine and nimodipine enantiomers in rats plasma by high performance capillary electrophoresis

目的:建立血浆中尼群地平和尼莫地平对映体的毛细管电泳的手性分离方法。方法:以对硝基苯甲酸为内标,血浆样品碱化后以乙醚溶剂提取2次,运行缓冲液为40 mmol.L-1磷酸二氢钠(用磷酸调节pH至2.96)-10 mmol.L-1磺丁基醚-β-环糊精(SBE-β-CD),检测波长为237 nm,尼群地平分离电压为-18 kV,尼莫地平分离电压为-15 kV,电动进样10 s。结果:尼群地平和尼莫地平两对映体均达到基线分离,且不受杂质干扰,尼群地平和尼莫地平浓度分别在28.4～568 ng.mL-1和27.4～548 ng.mL-1范围内线性良好,最低检测浓度分别为11.4 ng.mL-1和11.0 ng.mL-1。结论:本方法快速、简单及低耗,可适用于尼群地平和尼莫地平在体内立体选择性的研究。

Objective：To establish a capillary electrophoresis method for the chiral separation and determination of nitrendipine and nimodipine enantiomers in rats plasma.Method：The biological samples were alkalized and extracted with ethyl ether by twice.The running buffer was composed of 40 mmol·L-1 sodium dihydrogen phosphate（adjusted to pH 2.96 with phosphoric acid）-10 mmol·L-1 sulfobutyl ether-β-cyclodextrin（SBE-β-CD）.The detection wavelength was 237 nm.The applied voltage of nitrendipine and nimodipine enantiomers were-18 kV and-15 kV,respectively.Samples were injected into capillary with electric power for 10 s.p-Nitrobenzoic acid was used as internal standard.Result：Enantiomers of nitrendipine and nimodipine were separated at a base line under the above condition,and the determination was not interfered by endogenous components from rats.The linear concentration range of nitrendipine and nimodipine were 28.4-568 ng·mL-1 and 27.4-548 ng·mL-1,with the detection limit of 11.4 ng·mL-1 and 11.0 ng·mL-1.Conclusion：This method is quick,simple and low consumption,applicable to the stereoselectivity study of nitrendipine and nimodipine in vivo.