Chiral separation of β-amino alcohols by capillary electrophoresis using cyclodextrins as buffer additives. I. Effect of varying operating parameters

Abstract

Capillary electrophoresis has been used for the chiral analysis of two β-amino alcohol pharmaceutical compounds. Capillary zone electrophoresis conditions were used with β-cyclodextrin as a chiral mobile phase additive. The effects of variation of β-cyclodextrin concentration, temperature, pH, background electrolyte composition and concentration have been investigated. Optimum separations were achieved for clenbuterol using β-cyclodextrin at its solubility limit (16mM), the lowest practicable temperature (19°C), pH 4.0 and an electrolyte solution with a high ionic strength prepared from 0.1 M citric acid and 0.3 M Na2HPO4. For the development compound picumeterol and its (S)-enationmer, the optimum pH 4.0 buffer was prepared from 0.1 M citric acid and 0.2 M sodium acetate. Baseline separation with resolution greater than 2 was achieved for both compounds.