Biofuel cell based on glucose oxidase and microperoxidase-11 monolayer-functionalized electrodes

Apoglucose oxidase was reconstituted onto a pyrroloquinoline quinone and flavin adenine dinucleotide phosphate, PQQ-FAD, monolayer associated with a rough Au electrode to yield a bioelectrocatalytically active glucose oxidase, GOx. Electrically contacted PQQ-FAD/GOx monolayer was applied to the biocatalytic oxidation of glucose. A microperoxidase-11, MP-11, monolayer was assembled onto a rough Au electrode and used for the biocatalytic reduction of H₂O₂. Both biocatalytic electrodes, Au/PQQ-FAD/GOx and Au/MP-11, were assembled into a biofuel cell using glucose and H₂O₂ as the fuel substrate and the oxidizer, respectively. The biofuel cell generates an open-circuit voltage, V_oc, of ca. 310 mV and a short-circuit current density, i_sc, of ca. 114 μA cm^-2. The maximum electrical power, P_max, extracted from the cell is 32 μW at an external optimal load of 3 kΩ. The fill factor of the biofuel cell, f = P_max I_sc^-1 V_oc^-1, is ca. 25%.