高效毛细管电泳法拆分25R、25S鲁斯可皂苷元初步研究

目的：对高效毛细管电泳法拆分25R、25S-鲁斯可皂苷元混合物的条件进行探讨，以建立一种快速测定鲁斯可皂苷元差向异构体比例的方法。方法：以羟丙基-β-环糊精作为手性添加剂，考察分离电压、缓冲液pH、离子浓度、环糊精浓度对25R、25S-鲁斯可皂苷元拆分的影响。结果：从湖 北麦冬制备分离的鲁斯可皂苷元，NMR、IR检测结果显示其是以25S构型为主要成分、25R和25S 2个差向异构体并存的混合物。以0.018 mol·L^-1的羟丙基-β-环糊精为手性添加剂，分离电压6.0 kV，0.075 mol·L^-1的pH=10.0磷酸氢二钠缓冲液，25R与25S-鲁斯可皂苷元可实现基线分离（分离度1.52±0.13），在此条件下，测得制备的鲁斯可皂苷元中25R、25S异构体含量比为25.4：74.6。结论：高效毛细管电泳法可用于25R与25S-鲁斯克皂苷元手性拆分。研究结果为鲁斯可皂苷元药理学研究、鲁斯可皂苷元质量控制提供新方法。

Objective: To investigate a high performance capillary electrophoresis (HPCE) method for the chiral separation for 25R/25S-ruscogenin,in order to establish a rapid method to determine the ruscogenin isomer ratio. Methods: Using hydroxypropyl-β-cyclodextrin as the chiral additive,the HPCE conditions including separation voltage,pH and ion concentration of buffer as well as the concentration of the chiral additive were established to obtain an optimal HPCE method for the chiral separation of 25R/25S-ruscogenin. Results: Ruscogenin from Liriope spicata was identified as the mixture of 25R/25S epimerides according to its IR and NMR data.The resolution of 25R and 25S-ruscogenins could reach to 1.52±0.13 under the condition of 6.0 kV separation voltage,0.075 mol·L^-1 phosphate buffer at pH=10.0 and 0.018 mol·L^-1 HP-β-CD as the chiral additive.The ratio of 25R to 25S epimeride of ruscogenin was 25.4:74.6 according to their areas in the HPCE spectrum. Conclusion: The 25R and 25S epimerides of ruscogenin can be separated by HPCE method.Our study would provide a new sight for the pharmaceutical research and contribute to the quality control of ruscogenin.