Chiral selective separation of tocainide by capillary electrophoresis using various cyclodextrin derivatives

Chiral separation of tocainide, an antiarrythmic agent, was solved using the capillary electrophoresis method. Fifteen types of cyclodextrins were tried as chiral selective buffer additives, and baseline separation was achieved with five of them. The variables that were studied comprise, type and concentration of the chiral selectors, pH of the buffers, and the organic modifiers. The best resolution, an R(s) value of 5.2, was achieved using 7.5 mM gamma -cyclodextrin phosphate at pH 6.8. Migration reversal of enantiomers was observed when changing the type of cyclodextrins, Not only the tocainide but also its by-product were enantiomericaly separated. (C) 2001 John Wiley & Sons, Inc.