title: Simultaneous determination of disopyramide and mono-N-dealkyldisopyramide enantiomers in human plasma by capillary electrophoresis.
abstract: In this paper, a rapid method for the enantioselective analysis of the antiarrhythmic drug disopyramide and its main metabolite mono-N-dealkyldisopyramide in human plasma by capillary electrophoresis employing the cyclodextrin-modified electrokinetic chromatography mode is described. Sample clean-up was carried out by alkalinization with sodium hydroxide followed by liquid-liquid extraction with toluene. The complete enantioselective analysis was performed within less than 5 min using 20 mmol/L sodium acetate buffer, pH 5.0, containing 0.2% w/v sulfated beta-cyclodextrin as chiral selector. A 40 cm uncoated fused-silica capillary was used for the analysis, performed at a voltage of 15 kV and at 20 degrees C. The calibration curves were linear over the concentration range of 62.5-1850 ng/mL and 125-1850 ng/mL for each enantiomer of disopyramide and mono-N-dealkyldisopyramide. The mean recoveries for disopyramide and mono-N-dealkyldisopyramide enantiomers were up to 87 and 69%, respectively. All four enantiomers studied could be quantified at three different concentrations (200, 400 and 600 ng/mL) with coefficient of variation and % relative error not higher than 15%. The quantitation limit was 62.5 ng/mL for (+)-(S)-and (-)-(R)-disopyramide and (-)-(R)-mono-N-dealkyldisopyramide and 125 ng/mL for (+)-(S)-mono-N-dealkyldisopyramide, using 1 mL of human plasma.
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, SP, Brazil.
authors.forename: V A
authors.initials: VA
authors.lastname: Jabor
authors.forename: V L
authors.initials: VL
authors.lastname: Lanchote
authors.forename: P L
authors.initials: PL
authors.lastname: Bonato
mesh_terms: D004206:Disopyramide / Q000031:analogs & derivatives* / Q000097:blood*; D019075:Electrophoresis, Capillary / Q000379:methods; D006801:Humans
chemical_list: C030438:4-(isopropylamino)-2-(2-pyridyl)-2-phenylbutyramide; D004206:Disopyramide