Universal Electrode Based on Ferredoxin-NADP+ Oxidoreductase Enables Enzymatic Biofuel Cells With Broad Substrate Spectrum

Enzymatic biofuel cells face substrate limitations due to enzyme specificity of the electrode. A universal electrode was designed by immobilizing ferredoxin-NADP + oxidoreductase (FNR) with bacterial cellulose (BC), carbon nanotubes (CNTs), and silver nanowires (AgNWs). The electrode coupled with NADPH-dependent malic enzyme or glucose dehydrogenase generated electricity using malic acid and glucose, respectively. The open-circuit voltage reached 79.36 and 75.8 mV, respectively, and the accumulation of pyruvate and gluconate reached 0.30 and 0.25 mM, respectively, after 12 h. This strategy enables electron transfer from diverse substrates via NADPH.