Influence of the nature of the electrolyte on the chiral separation of basic compounds in nonaqueous capillary electrophoresis using heptakis(2,3-di-O-methyl-6-O-sulfo)-beta-cyclodextrin.
The influence on the enantiomeric resolution of the nature of the cationic BGE component (sodium, ammonium or potassium) and that of the anionic component (chloride, formate, methanesulfonate or camphorsulfonate) as well as the concentration of heptakis(2,3-di-O-methyl-6-O-sulfo)-beta-cyclodextrin (HDMS-beta-CD), the selected chiral selector, was studied in nonaqueous capillary electrophoresis (NACE). For this purpose, two D-optimal designs with 33 and 26 experimental points were applied. Three beta-blockers (atenolol, celiprolol and propranolol) and three local anesthetics (bupivacaine, mepivacaine and prilocaine) were selected as basic model compounds. Both cationic and anionic BGE components were found to have a deep impact on the enantiomeric resolution of the investigated analytes but it is the cationic component that has shown the strongest influence. Indeed, in some cases, the change of the latter led to a complete loss of enantioresolution. Based on the observed results, two NACE systems were recommended, namely ammonium formate and potassium camphorsulfonate in a methanolic solution containing HDMS-beta-CD and acidified with formic acid, in order to separate efficiently the enantiomers of basic drugs.
Servais
Anne-Catherine
AC
Department of Analytical Pharmaceutical Chemistry, Institute of Pharmacy, University of Liège, Avenue de l'Hopital 1, CHU, B36, B-4000 Liège 1, Belgium.
Fillet
Marianne
M
Chiap
Patrice
P
Dewé
Walthère
W
Hubert
Philippe
P
Crommen
Jacques
J
D004573:Electrolytes / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D004364:Pharmaceutical Preparations / Q000302:isolation & purification*; D013237:Stereoisomerism; D047392:beta-Cyclodextrins / Q000737:chemistry*
D004573:Electrolytes; D004364:Pharmaceutical Preparations; D047392:beta-Cyclodextrins; C447200:heptakis(2,3-diacetyl-6-sulfo)-cyclodextrin