高效毛细管电泳法测定匹伐他汀钙对映体异构体含量

目的: 建立高效毛细管电泳测定匹伐他汀钙中(-)-(3S,5R)-对映体含量的方法。方法: 研究影响对映体拆分的手性选择剂的种类及浓度、缓冲液的浓度和pH、电泳工作电压、温度,选出手性拆分的最佳条件,采用未涂层毛细管柱(57 cm×75 μm,有效长度为50 cm),用50 mmol·L^-1磷酸二氢钠溶液(用磷酸调节pH至3.0,含有50 mmol·L^-1γ-环糊精)作为填充缓冲液;50 mmol·L^-1的磷酸二氢钠溶液(用磷酸调节pH至3.0)作为运行缓冲液;工作电压为20 kV,分离温度为20℃;压力进样方式,进样压力为3.4 kPa,时间为5 s;检测波长为245 nm。结果: 匹伐他汀钙2个对映异构体达到基线分离,迁移时间和峰面积的RSD小于2%,最低检测限为0.1 μg·mL^-1。结论: 采用本方法可简便、准确地测定匹伐他汀钙中(-)-(3S,5R)-对映体的含量。

Objective: To establish a high performance capillary electrophoresis(HPCE)method for the determination of (-)-(3S,5R)-enantiomer of pitavastatin calcium. Methods: Both the complexation and resolution were affected by the CD type,CD concentration,pH and concentration of electrophoresis running buffer.The influence of working voltage and capillary temperature on the enantiomeric separation was also investigated.The filling buffer was 50 mmol·L^-1 NaH₂PO₄ solution(pH adjusted to 3.0 with H₃PO₄)containing 50 mmol·L^-1γ-CD and the running buffer was 50 mmol·L^-1 NaH₂PO₄ solution(pH adjusted to 3.0 with H₃PO₄).An uncoated capillary was used 57 cm×75 μm(50 cm to the detector).Detection was carried out with a UV detector at 245 nm.The separation was performed at 20℃ with a positive voltage of 20 kV.Samples were injected into the capillary by pressure at 3.4 kPa for 5 s. Results: The enantiomers of pitavastatin calcium were well separated.The RSDs for migratory time and peak response were lower than 2%.The minimum detectable concentration was 0.1 μg·mL^-1. Conclusion: The method is simple and accurate,and can be applied to the determination of (-)-(3S,5R)-enantiomer in pitavastatin calcium.