Effect of (+) or (−) camphorsulfonic acid additives to the mobile phase on enantioseparations of some basic drugs on a Chiralcel OD column

This paper describes the modification of Chiralcel OD column properties by adsorption of (+) or (−) camphorsulfonic acids (CSAs) used as additives to the mobile phase. The effects on retention, selectivity and efficiency, of adsorption of (+) and (−) CSAs on a Chiralcel OD column were examined. Racemic anti-histamines, anti-malarial and anti-fungal drugs, namely doxylamine, miconazole, sulconazole, hydroxyzine, homochlorcyclizine, methoxypheniramine, cyclopentolate and ephedrine were investigated as chiral tested compounds. All the studied drugs have an amino nitrogen atom in their structure. Only the enantioseparation of ephedrine enantiomers with CSAs alone was studied on the Nucleosil stationary phase, and these results were compared with the results obtained on the Chiralcel OD phase. A new dynamically generated stationary phase, with very good enantioseparation ability towards the studied compounds, was obtained by the adsorption of (−) CSA on the Chiralcel OD column.