title: Amperometric tyrosinase biosensor based on polyacrylamide microgels.
abstract: An amperometric enzyme sensor using tyrosinase (PPO) entrapped in polyacrylamide microgels has been developed for determination of phenolic compounds. Polyacrylamide microgels were obtained by the concentrated emulsion polymerization method. The crosslinking of the polymer matrix optimum to retain the enzyme and to allow the diffusion of the compounds involved in the enzyme reaction has been studied (4.0%) as well as the influence on the response of analytical parameters such as pH, temperature, enzyme load and working potential. The useful lifetime of the biosensor was 27 days and it was useful to determine monophenolics compounds (e.g. cresol, chlorophenol) and diphenolics compounds (e.g. catechol and dopamine) by amperometric measurements at -100mV (versus SCE) in a batch system. The results showed that the substrate structures have a great influence on the sensor response.
authors.affiliation: Departamento de Química Analítica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain.
authors.forename: J P
authors.initials: JP
authors.lastname: Hervás Pérez
authors.forename: M
authors.initials: M
authors.lastname: Sánchez-Paniagua López
authors.forename: E
authors.initials: E
authors.lastname: López-Cabarcos
authors.forename: B
authors.initials: B
authors.lastname: López-Ruiz
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D014442:Monophenol Monooxygenase / Q000737:chemistry*; D010316:Particle Size; D010636:Phenols / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000180:Acrylic Resins; D004800:Enzymes, Immobilized; D010636:Phenols; C016680:polyacrylamide gels; D014442:Monophenol Monooxygenase