title: Chiral counter-current chromatography of gemifloxacin guided by capillary electrophoresis using (+)-(18-crown-6)-tetracarboxylic acid as a chiral selector.
abstract: (+)-(18-crown-6)-tetracarboxylic acid (18C6H4) has been known as a highly efficient chiral selector for resolving primary amine enantiomers in capillary electrophoresis (CE). We investigated the chiral separation of gemifloxacin using 18C6H4 in analytical counter-current chromatography (CCC). The separation conditions for CE, including the binding constant, pH, and run buffer constituents, provided a helpful guideline for chiral CCC. A successful separation of gemifloxacin enantiomers could be achieved using a two-phase solvent system composed of 1-butanol-ethyl-acetate-bis(2-hydroxyethyl)aminotris(hydroxymethyl)methane acetate buffer with a small amount of 18C6H4. The hydrophobicity of the solvent system and the 18C6H4 concentration were varied to optimize the chiral separation.
authors.affiliation: School of Chemistry, Seoul National University, Seoul 151-747, South Korea.
authors.forename: Eunsook
authors.initials: E
authors.lastname: Kim
authors.forename: Yoon-Mo
authors.initials: YM
authors.lastname: Koob
authors.forename: Doo Soo
authors.initials: DS
authors.lastname: Chung
mesh_terms: D002021:Buffers; D003377:Countercurrent Distribution / Q000379:methods*; D043844:Crown Ethers / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D024841:Fluoroquinolones / Q000032:analysis*; D000077735:Gemifloxacin; D006863:Hydrogen-Ion Concentration; D009287:Naphthyridines / Q000032:analysis*
chemical_list: D002021:Buffers; D043844:Crown Ethers; D024841:Fluoroquinolones; D009287:Naphthyridines; C090732:18-crown-6 2,3,11,12-tetracarboxylic acid; D000077735:Gemifloxacin