title: Determination of codeine and its metabolite in human urine by CE with amperometric detection.
abstract: The amperometric detection of codeine and its metabolite, morphine following capillary zone electrophoretic separation is described. A carbon-disk electrode used as working electrode for two analytes exhibited a good response at 0.90 V (vs. Ag/AgCl). The optimal conditions of separation and detection were pH 8.4 phosphate buffer solution (0.06 mol x l(-1)), 12 kV for the separation voltage, sample injection at 12 kV for 10 s. The linear ranges were from 3.1 x 10(-7) to 2.5 x 10(-5) mol x l(-1) for codeine and 1.9 x 10(-7) to 1.5 x 10(-5) x mol l(-1) for morphine with a correlation coefficient of 0.9996 and 0.9999, respectively. The detection limits for codeine and morphine were 1.6 x 10(-7) and 6.8 x 10(-8) x mol l(-1). The method developed was successfully applied to the determination of codeine and its metabolite, morphine in the human urine without any other sample pretreatment except filtration, and the results were satisfactory.
authors.affiliation: Department of Chemistry, East China Normal University, 200062, Shanghai, PR China.
authors.forename: Tianshu
authors.initials: T
authors.lastname: Zhou
authors.forename: Hui
authors.initials: H
authors.lastname: Yu
authors.forename: Qin
authors.initials: Q
authors.lastname: Hu
authors.forename: Yuzhi
authors.initials: Y
authors.lastname: Fang
mesh_terms: D000701:Analgesics, Opioid / Q000302:isolation & purification / Q000652:urine*; D003061:Codeine / Q000302:isolation & purification / Q000652:urine*; D004563:Electrochemistry; D004566:Electrodes; D019075:Electrophoresis, Capillary; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009020:Morphine / Q000032:analysis; D011199:Potentiometry; D012044:Regression Analysis; D015203:Reproducibility of Results; D012997:Solvents
chemical_list: D000701:Analgesics, Opioid; D012997:Solvents; D009020:Morphine; D003061:Codeine