Direct electron transfer of bilirubin oxidase (Myrothecium verrucaria) at an unmodified nanoporous gold biocathode

Well defined mediatorless bioelectrocatalytic reduction of oxygen with high current densities of 0.8 mA cm− 2 was obtained on nanoporous gold electrodes modified with Myrothecium verrucaria bilirubin oxidase. A stable faradaic response was observed when the enzyme modified electrode was coated with a specifically designed electrodeposition polymer layer. The response of the enzyme electrode was only slightly inhibited by the addition of F−.

► Direct O2 reduction by bilirubin oxidase at unmodified nanoporous Au electrode.
► High faradaic response of 0.8 mA cm–2 limited by diffusion of oxygen.
► Significantly reduced inhibition by fluoride.