title: Sensitized phosphorescence as detection method for the enantioseparation of bupropion by capillary electrophoresis.
abstract: A new CE detection method was developed for the chiral drug bupropion (a second-generation antidepressant), based on phosphorescence both in the direct and in the sensitized mode using pulsed laser excitation at 266 nm. Electrokinetic chromatography using 5 mM sulfated-α-CD as chiral selector in 25 mM phosphate buffer at pH 3 allowed the separation of bupropion enantiomers with a high chiral resolution (Rs>3). In the sensitized phosphorescence detection mode, excitation energy is transferred from the analyte to an acceptor (1-bromo-4-napthhalenesulfonic acid or biacetyl) followed by time-resolved phosphorescence detection under deoxygenated buffer conditions. Using 2 × 10(-4) M biacetyl as the acceptor an LOD of 2 × 10(-7) M was obtained for each enantiomer, about 40 times better than in the direct mode. Under these separation conditions, no significantly different phosphorescence lifetimes (measured on-line) were obtained for the two bupropion enantiomers. The suitability of the method was demonstrated with the quantification of bupropion in a pharmaceutical formulation and its determination in a spiked urine sample.
authors.affiliation: Department of Biomolecular Analysis and Spectroscopy, Laser Centre Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
authors.forename: María
authors.initials: M
authors.lastname: Castro-Puyana
authors.forename: Ivonne
authors.initials: I
authors.lastname: Lammers
authors.forename: Joost
authors.initials: J
authors.lastname: Buijs
authors.forename: Cees
authors.initials: C
authors.lastname: Gooijer
authors.forename: Freek
authors.initials: F
authors.lastname: Ariese
mesh_terms: D016642:Bupropion / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000652:urine; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D008163:Luminescent Measurements / Q000379:methods*; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D013607:Tablets; D047391:alpha-Cyclodextrins / Q000737:chemistry
chemical_list: D013607:Tablets; D047391:alpha-Cyclodextrins; D016642:Bupropion