高效毛细管电泳法测定甲磺酸罗哌卡因旋光异构体含量

HPCE Determination of R-(+)-Ropivacaine Mesylate in S-(-)-Ropivacaine Mesylate

目的:建立一种用高效毛细管电泳法测定甲磺酸罗哌卡因中 R-(+)-对映体含量的方法。方法:研究了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,最终选择手性拆分的最佳条件,即用含50mmol·L^(-1)DM-β-CD 的25mmol·L^(-1)的磷酸二氢钠溶液(用磷酸调节 pH 为2.5)作为填充缓冲液;25mmol·L^(-1)的磷酸二氢钠溶液(用磷酸调节 pH 为2.5)作为运行缓冲液;工作电压30 kV;温度为20℃;检测波长215 nm;电动进样,进样电压10 kV,进样时间10 s。结果:使甲磺酸罗哌卡因两个对映异构体达到基线分离,迁移时间和峰面积的 RSD 小于5%,最低检测限为1μg·mL^(-1)。结论:采用本方法可简便、准确地测定甲磺酸罗派卡因中 R-(+)-对映体的含量。

To establish a high performance capillary electrophoresis（HPCE） method for determining of the dextro - enantiomer of ropivacaine mesylate. Method： Both complexation and resolution were affected by the CD type,CD concentration and the pH and concentration of electrophoretic running buffer. The influence of working voltage and capillary temperature on the enantiomeric separation was also investigated. The filling buffer was 25 mmol · L^-1 NaH2PO4 solution（ adjusted pH to 2. 5 with H3PO4） containing 50 mmol · L^-1 DM -β -CD and the running buffer was 25 mmol · L^-1 NaH2PO4 solution（ adjusted pH to 2. 5 with H3PO4 ）. An uncoated capillary used was 57 cm ×50 μm（50 cm to the detector）. Detection was carried out with a UV detector at 215 nm. The separation was performed at 20 ℃ with a positive voltage of 30 kV. Samples were injected into the capillary by electrokinetic force at 10 kV for 10 s. Results： The enantiomers of ropivacaine mesylate was separated well. The RSD for migratory time and peak response were lower than 5%. The lowest detective concentration was 1 μg · mL^-l. Conclusion：The method is simple and accurate and can be applied to the assay of R - （ ＋ ） - ropivacaine in ropivacaine mesylate.