Enantioseparation of amlodipine maleate by capillary electrophoresis using colominic acid as a chiral selector and the mechanism of chiral recognition

AimColominic acid, a novel chiral selector, was applied to enantioseparation of dihydropyridine derivative by capillary electrophoresis. A new method was developed for enantioseparation of amlodipine maleate, a novel calcium channel blocking therapeutic agent. The chiral recognition mechanism of colominic acid to amlodipine maleate was studied. MethodsCapillary electrophoresis was performed, and the effects of separation conditions on chiral separation were examined, including concentration of chiral selector, buffer pH, capillary temperature, applied voltage and molecular mass of colominic acid. ResultsThe optimum conditions were additive concentration of 8.0%, buffer pH at 3.00, capillary temperature at 15 ℃, 12 kV for applied voltage and 3×104 for molecular mass of colominic acid. Under optimum conditions complete separation was achieved between the enantiomers of amlodipine maleate with resolution as high as 2.20. ConclusionThe cliral separation was based on the multipoint recognition between colominic acid and amlodipine maleate. It is recommended that this simple, rapid and selective method be used for enantioseparation of amlodipine maleate. As far as polysaccharides were concerned, colominic acid was first used for enantioseparation of amlodipine maleate.