Immobilisation of Flavin-Adenine-Dinucleotide-Dependent Glucose Dehydrogenase alpha Subunit in Free-Standing Graphitised Carbon Nanofiber Paper Using a Bifunctional Cross-Linker for an Enzymatic Biofuel Cell

Abstract

Free-standing graphitised carbon nanofiber paper (GCNFp) is fabricated using a dispersion-filtration method and modified by non-covalent functionalisation with 1-pyrenebutyric acid N-hydroxysuccinimide estera bifunctional linker reagentthrough - stacking. This modified GCNFp is then used to immobilise enzymes, and together they form an electrode for enzymatic biofuel cell (EBFC) applications. This fabrication method is shown to be capable of providing a practical platform for enzyme-electrode electrical communication that is faster than comparable systems based on other carbon materials, as calculated from the heterogeneous electron-transfer rate constant. The GCNFp-based EBFC reaches a maximum power density at a glucose concentration of 100mM, yielding 834.9 +/- 200, 262.9 +/- 15.6 and 147.2 +/- 4.70Wcm(-2) for flavin-adenine-dinucleotide-dependent glucose dehydrogenase (FADGDH)-menadione, glucose oxidase (GOX)-menadione, and GOX-only systems (as the anode), respectively, with laccase as the cathode.