title: Determination of ibuprofen and tetrazepam in human urine by micellar electrokinetic capillary chromatography.
abstract: A new micellar electrokinetic capillary chromatography method (MEKC) is proposed for the determination of ibuprofen and tetrazepam in human urine samples over a concentration range of therapeutic interest. A fused silica capillary (60 cm x 75 microm) is used. Ibuprofen and tetrazepam are detected via UV detection at 220 and 228 nm, respectively. Separation is performed at 25 degrees C and at a separation voltage of 30 kV, with 15 mM borate buffer (pH 10.2) containing 40 mM sodium dodecylsulfate as the electrolyte solution. Under these conditions the analytes were separated in <11 min. Sulfamethazine is used as an internal standard. Prior to determination, the samples are purified and enriched by means of an extraction-preconcentration step with a preconditioned C18 cartridge and by eluting the compounds with methanol. Good linearity, accuracy, precision, robustness and solution stability were achieved for the technique. Detection limits of 200 microg L(-1) for ibuprofen and 300 microg L(-1) for tetrazepam were obtained. These analytes were then determined in real urine using the technique.
authors.affiliation: Departamento de Química Analítica y Tecnología de Alimentos, Universidad de Castilla-La Mancha, 13071, Ciudad Real, Spain. JuanJose.Berzas@uclm.es
authors.forename: J J
authors.initials: JJ
authors.lastname: Berzas Nevado
authors.forename: J
authors.initials: J
authors.lastname: Rodríguez Flores
authors.forename: G
authors.initials: G
authors.lastname: Castañeda Peñalvo
authors.forename: R M
authors.initials: RM
authors.lastname: Rodríguez Dorado
mesh_terms: D001569:Benzodiazepines / Q000737:chemistry / Q000652:urine*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D006801:Humans; D007052:Ibuprofen / Q000737:chemistry / Q000652:urine*; D012680:Sensitivity and Specificity; D012996:Solutions; D013696:Temperature; D013997:Time Factors
chemical_list: D012996:Solutions; D001569:Benzodiazepines; C005245:tetrazepam; D007052:Ibuprofen