Direct Electron Transfer of Trametes hirsuta Laccase in a Dual-Layer Architecture of Poly(3,4-ethylenedioxythiophene) Films

Abstract

Direct electron transfer (DET) type biocatalysis was accomplished for Trametes hirsuta laccase (ThL) on a glassy carbon (GC) electrode by immobilizing laccase into a well-designed dual-layer architecture of poly(3,4-ethylenedioxythiophene) (PEDOT). PEDOT films were subsequently deposited on a GC electrode via electropolymerization, with NO3− as the counterion for the first accommodation layer and poly(styrene-sulfonate) anions (PSS−) for the second capping layer. The enzyme (ThL) was cast on top of the accommodation layer (PEDOT-NO3), and then the capping layer (PEDOT-PSS) was electrodeposited to entrap ThL between the layers. This enzyme electrode is reported to be able to promote DET between ThL and the GC electrode and catalyze the reduction of O2 into water. The influence of fabrication parameters on the enzyme electrode performance was investigated through chronoamperometric measurements. The investigated parameters included different combinations of PEDOT films, ThL loading, and the thicknesses of b...