Maghemite as a catalyst for glucose oxidation in a microfluidic fuel cell

We evaluated the performance of glucose/O2 fuel cells, constructed as fluidic chips with controllable fuel flow and comprising a maghemite (γ-Fe2O3) nanoparticle/GOx-coated anode and Pt nanoparticles as the cathode. Maghemite is a biocompatible material that mediates electron transfer during glucose oxidation. The open-circuit voltage of the cell was 0.30 V, with a maximum power density of 30 μW cm−2 at pH 7.4. The voltage cell and power density were compared with those of other microfluidic fuel cells. During continuous operation, the current density of the cell decreased to 50%, likely due to swelling of the enzyme bilayer.