GAS-CHROMATOGRAPHIC SEPARATION OF THE ENANTIOMERS OF VOLATILE FLUOROETHER ANESTHETICS BY DERIVATIZED CYCLODEXTRINS .2. PREPARATIVE-SCALE SEPARATIONS FOR ISOFLURANE

Preparative-scale gas chromatographic separation of the enantiomers of isoflurane, a volatile anesthetic, has been achieved with 2 m x 10 mm I.D. columns, packed with 80-100 mesh Chromosorb WAW, coated with up to 23% (w/w) trifluoroacetyl gamma-cyclodextrin as stationary phase. T he type and particle size of the support, the concentration of the sta tionary phase and the separation conditions were varied to improve pro duct purity and the production rate under overloaded elution mode cond itions. Using a sampling interface located between the exit of the pre parative column and the fraction collector, effluent samples were dire cted onto a short, high-efficiency analytical capillary column every 3 0 s to achieve on-line enantiomeric analysis of the eluting bands, whi ch allowed the calculation of purity, recovery and production rate for the separations.