Development of Fructose Dehydrogenase-Ferrocene Redox Polymer Films for Biofuel Cell Anodes

Novel amperometric fructose electrodes were built by immobilizing fructose dehydrogenase (FDH) in crosslinked films of ferrocene-modified linear poly(ethylenimine) (Fc-C 6 -LPEI). The results showed that the electrochemical and enzymatic response of the sensors was dependent upon the pH of both the enzyme solution and redox polymer solution used to form the crosslinked films. The optimized redox polymer-enzyme film was able to effectively shuttle the electron from the active sites of fructose dehydrogenase to the electrode surface producing current densities of 245 μA/cm 2 in response to saturating fructose concentrations. We also demonstrate that when crosslinked Fc-C 6 -LPEI/FDH films were formed on networks of single-walled carbon nanotubes the current response to fructose increased ∼4 fold reaching a current density of 1.0 mA/cm. 2 Finally we demonstrate that the films could be utilized as bioanodes in enzymatic biofuel cells and produce a power density of 29 μW/ cm 2 .