title: Laccase-based biosensor for the determination of polyphenol index in wine.
abstract: In this work we have developed and characterized the use of Laccases from Trametes versicolor (TvL) and Trametes hirsuta (ThL) as biocatalytic components of electrochemical biosensors for the determination of polyphenol index in wines. Polyazetidine prepolimer (PAP) was used as immobilizing agent, multi-walled and single-walled carbon nanotubes screen-printed electrodes as sensors (MWCNTs-SPE and SWCNTs-SPE) and gallic acid as standard substrate. The amperometric measurements were carried out by using a flow system at a fixed potential of -100 mV vs. silver/silver chloride electrode in Britton-Robinson buffer 0.1 mol L(-1), pH 5. The results were compared with those obtained with the Folin-Ciocalteau reference method. The results obtained in the analysis of twelve Italian wines put in evidence the better suitability of ThL-MWCNTs-based biosensor in the determination of the polyphenol index in wines. This biosensor shows fast and reliable amperometric responses to gallic acid with a linear range 0.1-18.0 mg L(-1) (r(2)=0.999). The influence of the interferences on both spectrophotometric and electrochemical measurements have been carefully evaluated.
authors.affiliation: Sapienza Università di Roma, Dipartimento di Chimica e Tecnologie del Farmaco, Piazzale Aldo Moro 5, 00185 Roma, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Di Fusco
authors.forename: Cristina
authors.initials: C
authors.lastname: Tortolini
authors.forename: Daniela
authors.initials: D
authors.lastname: Deriu
authors.forename: Franco
authors.initials: F
authors.lastname: Mazzei
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004563:Electrochemistry; D005419:Flavonoids / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D042845:Laccase / Q000378:metabolism*; D037742:Nanotubes, Carbon / Q000737:chemistry; D010636:Phenols / Q000032:analysis*; D011094:Polyethyleneimine / Q000737:chemistry; D059808:Polyphenols; D055454:Trametes / Q000201:enzymology; D014920:Wine / Q000032:analysis*
chemical_list: D005419:Flavonoids; D037742:Nanotubes, Carbon; D010636:Phenols; D059808:Polyphenols; D011094:Polyethyleneimine; D042845:Laccase