Current location: JICS Archive > Vol. 5 > No. 4 > Articles : 3

Enantiomeric Separation of Racemic Clenbuterol by Capillary Zone Electrophoresis

F. Jiao^a,b, X. Chen^a,*, Y. Hu^b and Z. Wang^a

^aSchool of Chemistry & Chemical Engineering
^bSchool of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China

A method for capillary electrophoretic enantiomeric separation of a racemic clenbuterol has been established with hydroxypropyl-β-cyclodextrin as the chiral selector. General equations and data analysis are presented to relate mobility to the equilibrium constants in simple binding equilibria and used to determine binding constants and thermodynamic parameters for host-guest complexation of clenbuterol enantiomers with hydroxypropyl-β-cyclodextrin as a selector. The effects of β-cyclodextrin type and concentration, buffer type, concentration and pH, as well as separation voltage and capillary temperature were investigated in detail. A maximal resolution of 6.78 was obtained. The binding constants of the host-guest complex of clenbuterol enantiomers with hydroxypropyl-β-cyclodextrin, K_R-CD and K_S-CD are 22.50 and 43.09 l mol^-1, respectively.

Keywords: Electrophoretic enantiomeric separation, Clenbuterol enantiomers, Hydroxypropyl-β-cyclodextrin, Binding constants, Thermodynamic parameters