title: Amperometric PMMA-microchip with integrated gold working electrode for enzyme assays.
abstract: The use of a gold film in-channel detector combined with a poly(methyl methacrylate) (PMMA) CE microchip has been tested for alkaline phosphatase (AP) enzymatic assays. Tris-borate or Tris-Gly (pH 9.0, 50 mmol L(-1)) buffer solutions were appropriate as running buffer. Signals for three common AP products: alpha-naphthol, p-nitrophenol, and ascorbic acid, were obtained. They were reproducible (RSD 4.4% for six successive electropherograms corresponding to 5 mmol L(-1) alpha-naphthol solution) and the response was dependent on concentration (linear relationship for ascorbic acid solutions between 5 and 20 mmol L(-1) concentration). Use of an end-channel gold film electrode was also investigated. If one of the reagents (substrate or enzyme) is included in the running buffer, two different types of enzymatic assay are feasible in less than 3 min.
authors.affiliation: Departamento de Química Física y Analítica, Universidad de Oviedo, 33006, Oviedo, Asturias, Spain.
authors.forename: Mario
authors.initials: M
authors.lastname: Castaño-Alvarez
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Fernández-Abedul
authors.forename: Agustín
authors.initials: A
authors.lastname: Costa-García
mesh_terms: D004566:Electrodes; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D004798:Enzymes / Q000737:chemistry*; D006046:Gold; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D004798:Enzymes; D006046:Gold; D019904:Polymethyl Methacrylate