title: Analysis of polymyxin B sulfate by capillary zone electrophoresis with cyclodextrin as additive. Method development and validation.
abstract: A capillary zone electrophoresis method for analysis of polymyxin B sulfate is described. In this method, triethanolamine (TEA)-phosphate buffer at pH 2.5 was employed to reduce the adsorption of analyte onto the capillary wall. Methyl-beta-cyclodextrin (M-beta-CD) and 2-propanol (IPA) were found to be necessary for selectivity enhancement. In order to optimize the method and to control its robustness, a central composite design was performed with four parameters, i.e. concentration of M-beta-CD, TEA, IPA and buffer pH. The optimal separation conditions were as follows: capillary, 55 cm (50 microm I.D., 47 cm effective length); 130 mM TEA-phosphate buffer (pH 2.5) containing 5 mM M-beta-CD and 5% IPA; 24 kV (51 microA) applied voltage; column temperature, 20 degrees C. Further, linearity and limits of detection quantification were examined. Three commercial samples were analyzed quantitatively.
authors.affiliation: Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, Faculteit Farmaceutische Wetenschappen, Katholieke Universiteit Leuven, Belgium.
authors.forename: J W
authors.initials: JW
authors.lastname: Kang
authors.forename: A
authors.initials: A
authors.lastname: Van Schepdael
authors.forename: J A
authors.initials: JA
authors.lastname: Orwa
authors.forename: E
authors.initials: E
authors.lastname: Roets
authors.forename: J
authors.initials: J
authors.lastname: Hoogmartens
mesh_terms: D003505:Cyclodextrins / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D011112:Polymyxin B / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003505:Cyclodextrins; D011112:Polymyxin B