RT info:eu-repo/semantics/article
T1 Amperometric tyrosinase based biosensor using an electropolymerized phosphate-doped polypyrrole film as an immobilization support. Application for detection of phenolic compounds
A1 Rodríguez Méndez, María Luz
A1 Apetrei, Constantin
A1 Saja Sáez, José Antonio de
AB An amperometric biosensor was constructed by immobilization of enzyme, tyrosinase, in an electrochemically synthesized phosphate ion-doped polypyrrole film on a Pt disk electrode. The tyrosinase maintains its bioactivity well within the polypyrrole thin film. A clearly defined reduction current proportional to the phenolic compounds concentration was observed in cyclic voltammetry, which attributed to the reduction of enzymatically produced quinone at the electrode surface.Phenolic compounds were quantitatively estimated in aqueous medium by the direct electrochemical reduction of enzymatically liberated quinone species at −0.05 V by chronoamperometry. For the all six phenolic compounds analyzed, the kinetics of the enzymatic reaction fitted into a Michaelis–Menten type kinetics, as demonstrated by the h parameter close to 1 obtained from the Hill's plot.The sensitivity followed the decreasing order catechol > phenol > 2-bromophenol > 2-chlorophenol > 2-iodophenol > 2-fluorophenol. The greater value of Imax and the lowest  was found for catechol.The detection limits were in the range of 0.84–8.54 μM. The lowest detection limits were found for catechol and the highest for 2-fluorophenol.
SN 0013-4686
YR 2011
FD 2011
LK http://uvadoc.uva.es/handle/10324/30768
UL http://uvadoc.uva.es/handle/10324/30768
LA eng
NO Electrochimica Acta  vol. 56 p. 8919-8925
NO Producción Científica
DS UVaDOC
RD 23-nov-2024