CONICET | Buscador de Institutos y Recursos Humanos

Simple and fast methods for the monitoring ofphenol-like compounds are relevant in diverse fieldsranging from waste management to neurosciences. Laccasesare copper-containing enzymes, which, dependingon their origin, are able to oxidize different phenol compoundsat different pH conditions. Through adequate laccaseimmobilization, disposable screen printed electrodescan be used as interphase to build amperometric phenolsensors. In this work three different laccases were studiedfor the determination of phenol-like compounds, two ofthem are isoenzymes from Trametes trogii and the thirdone from Rhus vernicifera. Their immobilization onscreen printed electrodes is presented for the constructionof amperometric sensors. The electrode substrate is composedby graphite screen printed electrodes modifiedwith carbon nanotubes and silica microspheres where, dependingon the application, one of the three laccases isadsorbed. As each laccase shows an optimum workingpH, they were conveniently selected to determine dopamineat physiological pH and catechol at acid pH. Determinationsin the micromolar range were possible in bothcases. Chronoamperometry shows to be an effective techniquefor their determinations, simpler than other electrochemicalmethods already presented in the literature.