Capillary electrophoresis for analysis of optical impurity of L-pramipexole / 第二军医大学学报

ABSTRACT

Objective: To develop a capillary electrophoresis system for purity test and enantioseparation of L-pramipexole. Methods: Using β-CD, HP-β-CD, SBE-β-CD and DM-β-CD as chiral selection agents, we investigated the influence of concentration, pH of chiral selection agent and column length and inner diameter on chiral separation. The enantiomers were baseline separated under the following conditions-uncoated fused silica capillary (50 μm X 47 cm) with an effective length of 40 cm, back-ground electrolyte solution, 40 mmol/l trisodium citrate buffer solution, 0.5% SBE-β-CD, pH 4.0 adjusted by phosphoric acid, 5% methanol, 25 mmol·L-1 SDS, 40 mmol·L-1 sodium tetraborate solution as running buffer, and 16 kV separation voltage. The detection wavelength was set at 254 nm and the column temperature was 30*C. Results: The baseline separation of L-pramipexole was obtained under our condition. The optical isomerism had satisfactory resolution (Rs>2.5) and the content of R-pramipexole was less than 0.5%. Conclusion: The proposed method is simple, reliable and can be used for routine purity test and chiral separation.