Method development and validation for the chiral separation of peptides inthe presence of cyclodextrins using capillary electrophoresis and experimental design

The present study describes the application of statistical experimental des ign to the optimization of enantioselective separations of peptides in capi llary electrophoresis in order to obtain optimal operating conditions for r outine work. Hydroxypropyl-beta -cyclodextrin was used as chiral selector a nd Ala-PheOMe as model peptide. The experiments were performed according to a face centered cube response surface experimental design for obtaining in formation how the factors such as concentration of the chiral selector, pH, buffer concentration and voltage affected the two response goals, resoluti on and analysis time. In order to achieve the simultaneous optimization of these two major electrophoretic performance goals for efficient and fast se paration, the Derringer desirability functions were tested. While in the pr edefined experiments the analysis time for baseline separation was 25 min t he desirability functions proposed a CE method, which diminished the analys is time and permitted the complete separation of the peptide enantiomers wi thin 9 min. (C) 2001 Elsevier Science B.V. All rights reserved.