title: Amperometric tyrosinase based biosensor using an electrogenerated polythiophene film as an entrapment support.
abstract: An amperometric enzyme sensor using tyrosinase, also called polyphenol oxidase (PPO), was constructed for determination of phenolic compounds and herbicides. The enzyme was entrapped in a conducting polymer, poly 3,4-ethylenedioxythiophene (PEDT), electrochemically generated on a glassy carbon electrode. Several experimental parameters in the electropolymerisation process and working conditions were determined to optimise biosensor performances. Mono-phenol and di-phenol were tested in oxygenated solutions, by amperometric measurements at -200 mV (vs. SCE) in a batch system. The limit of detection of these molecules ranges from 5 to 500 nM. Detection of herbicides was obtained from the inhibition of tyrosinase electrode responses. The limit of detection for atrazine and diuron was 1 and 0.5 mgl(-1) respectively. These data suggest that PEDT film is a promising PPO immobilisation method.
authors.affiliation: ENSM-SE, 158 Cours Fauriel, 42023 Saint Etienne Cedex 2, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Védrine
authors.forename: Silvia
authors.initials: S
authors.lastname: Fabiano
authors.forename: Canh
authors.initials: C
authors.lastname: Tran-Minh