title: Influence of pH and pKa values on electrophoretic behaviour of quinolones in aqueous and hydro-organic media.
abstract: Through correct pH measurements, pKa and activity coefficient values, a model describing their effect on electrophoretic behaviour of substances is established. The suggested model uses the pH values in the acetonitrile-water mixtures used and takes into account the effect of activity coefficients. The model permits the calculation of acidity constants of analytes in hydro-organic media and also the prediction of the effect of pH on the electrophoretic mobility. The model is tested by determining the dissociation constants of a series of nine quinolones in acetonitrile-water mixtures of 0, 5.5, 10 and 30% (w/w) acetonitrile.
authors.affiliation: Department of Analytical Chemistry, Universitat de Barcelona, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Barrón
authors.forename: E
authors.initials: E
authors.lastname: Jiménez-Lozano
authors.forename: A
authors.initials: A
authors.lastname: Irles
authors.forename: J
authors.initials: J
authors.lastname: Barbosa
mesh_terms: D042462:4-Quinolones; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D009930:Organic Chemicals; D009994:Osmolar Concentration; D014867:Water
chemical_list: D042462:4-Quinolones; D000890:Anti-Infective Agents; D009930:Organic Chemicals; D014867:Water