title: Impurity profiling of atropine sulfate by microemulsion electrokinetic chromatography.
abstract: An oil-in-water microemulsion electrokinetic chromatography (MEEKC) method has been developed and validated for the determination of atropine, its major degradation products (tropic acid, apoatropine and atropic acid) and related substances from plants material (noratropine, 6-hydroxyhyoscyamine, 7-hydroxyhyoscyamine, hyoscine and littorine). Separation of atropine and all impurities was optimized by varying the voltage, the nature of the oil droplet and the buffer, as well as the organic modifier (methanol, 2-propanol or acetonitrile) and the surfactant type and concentration. The optimum O/W microemulsion background electrolyte (BGE) solution consists of 0.8% (w/w) octane, 6.62% (w/w) 1-butanol, 2.0% (w/w) 2-propanol, 4.44% (w/w) SDS and 86.14% (w/w) 10 mM sodium tetraborate buffer pH 9.2. In order to shorten the analysis time a voltage gradient was applied. The validation was performed with respect to specificity, linearity, range, limit of quantification and detection, precision, accuracy and robustness. The established method allowed the detection and determination of atropine sulfate related substances at impurity levels given in the European Pharmacopoeia. Good agreement was obtained between the established MEEKC method and the traditional RP-HPLC method.
authors.affiliation: Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
authors.forename: Yaser
authors.initials: Y
authors.lastname: Bitar
authors.forename: Ulrike
authors.initials: U
authors.lastname: Holzgrabe
mesh_terms: D001285:Atropine / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D004340:Drug Contamination / Q000517:prevention & control*; D004655:Emulsions; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004655:Emulsions; D001285:Atropine