Investigation of the chiral surfactant N-dodecoxycarbonylvaline in electrokinetic chromatography: improvements in elution range and pH stability via mixed micelles and vesicles, and the hydrophobicity determination of basic pharmaceutical drugs.

The chiral surfactant dodecoxycarbonylvaline (DDCV) has proven to be an effective pseudostationary phase for the separation of many enantiomeric pharmaceutical compounds. In this study the elution range and the prediction of octanol-water partitioning for the DDCV micellar system was examined. Through incorporation of DDCV in mixed micelles and unilamellar vesicles, enhancement of the elution range was observed. The mixed micelles contained a second anionic surfactant, sodium dodecyl sulfate (SDS), while the vesicles were composed of DDCV and the cationic surfactant cetyltrimethylammonium bromide (CTAB). Enantioselectivity, as well as other chromatographic and electrophoretic parameters, were compared between the mixed micelles, vesicles, and DDCV micelles. The hydrophobicity of the DDCV system was also evaluated as a predictor of n-octanol-water partition coefficients for 15 beta amino alcohols. The correlation between the logarithm of the retention factor (log k) and log P(ow) for seven hydrophobic beta-blockers and eight beta-agonists were r2 = 0.964 and r2 = 0.814, respectively.