Capillary electrophoresis of methylderivatives of quinolines. I

Migration behavior of quinoline, isoquinoline and related methylderivatives has been investigated with respect to the influence of running buffer acid ity and to the presence of polyethylene glycol (PEG) 2000 as additive. Diss ociation constants and ionic mobilities were determined by capillary electr ophoresis (CE). Mobility and viscosity measurements in PEG containing buffe rs show that analyte transport is not in accordance with Walden's rule and microviscosity plays the role in analyte retardation. Variation of pH and P EG concentration provides the optimal conditions for the CE separation of m ethylquinolines (0.0176 M acetate-Tris buffer, pH 5.5, 10% PEG 2000). Analy sis of industrial mixture (isoquinoline fraction from distillation of coal tar) was performed and good agreement with gas chromatographic results was found. (C) 2001 Elsevier Science B.V. All rights reserved.