title: Isotachophoresis of beta-blockers in a capillary and on a poly(methyl methacrylate) chip.
abstract: Analysis of the beta-blockers oxprenolol, atenolol, timolol, propranolol, metoprolol, and acebutolol in human urine by a combination of isotachophoresis (ITP) and zone electrophoresis (ZE) was investigated. Methods were developed with a conventional capillary electrophoresis (CE) apparatus and a poly(methyl methacrylate) (PMMA) microchip system. With CE the separation of oxprenolol, atenolol, timolol, and acebutolol from a standard solution containing 5 microg/mL of each compound was accomplished by performing ZE with transient ITP. The electrolyte system consisted of 10 mM sodium morpholinoethane sulfonate (pH 5.5) and 0.1% methylhydroxyethylcellulose as the leading electrolyte and 30 mM ortho-phosphoric acid (pH 2.0) as both the terminating and the ZE background electrolyte. With the microchip system the separation of oxprenolol and acebutolol from a standard solution containing 10 microg/mL of each compound was accomplished by a coupled-channel ITP-ZE device using the same leading electrolyte solution as the CE system but 5 mM glutamic acid (pH 3.4) as terminating and background electrolytes. The systems were used for analyses of patient urine samples. Water-soluble hydrophilic matrix compounds were removed from the urine samples by solid-phase extraction (SPE). Limits of quantification below 5 microg/mL could be achieved. The PMMA ITP-ZE chip has not earlier been used for analyses of any drugs from urine samples.
authors.affiliation: Technical Research Centre, VTT Processes, FIN-02044 VTT, Espoo, Finland.
authors.forename: Pirkko
authors.initials: P
authors.lastname: Kriikku
authors.forename: Benedikt
authors.initials: B
authors.lastname: Grass
authors.forename: Ari
authors.initials: A
authors.lastname: Hokkanen
authors.forename: Ingmar
authors.initials: I
authors.lastname: Stuns
authors.forename: Heli
authors.initials: H
authors.lastname: Sirén
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000032:analysis* / Q000652:urine; D000959:Antihypertensive Agents / Q000032:analysis; D004586:Electrophoresis / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D020366:Methylmethacrylate / Q000737:chemistry; D008832:Microchemistry
chemical_list: D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D020366:Methylmethacrylate