Thermophilic biocathode with bilirubin oxidase from Bacillus pumilus

Bilirubin oxidase (BOD) from Bacillus pumilus shows high thermostability in solution and high reactivity at high temperature for ABTS oxidation. When BOD is incorporated into a cross-linked redox-active hydrogel film consisting of pendant osmium moieties grafted on a polyvinylimidazole backbone on GC electrode, high catalytic current per enzyme molecule was achieved with redox mediator in a broad pH range from 4 to 7. The maximum current was increased with increasing the electrolyte temperature as high as 70 °C.

► Thermostable new BOD from Bacillus Pumilus is used. ► BOD can work well at elevated temperatures in solution and on modified electrodes. ► Diffusion-controlled oxygen reduction catalytic currents at 70 °C were observed.