Transparent and Capacitive Bioanode Based on Specifically Engineered Glucose Oxidase

• Here the authors detail an optimized transparent capacitive glucose oxidizing bioanode, capable of supplying current densities of 10 μA cm-​2 at applied potentials of 0.1 V-​0.2 V vs. SCE, when continuously performing in a simple phosphate buffer, pH 7.4 and artificial human tears, both with a glucose concn. of 0.05 mM only. When operating in pulse mode, the bioanode was able to deliver current densities ≤21 μA cm-​2 at the beginning of the pulse with 571 μC cm-​2 total charges stored. The biogenic part of the enzymic device was a recombinant glucose oxidase mutant from Penicillium amagasakiense with high catalytic efficiency towards glucose, up to 14.5x104 M-​1 s-​1. The nonbiogenic part of the anodic system was based on a poly(3,​4-​ethylenedioxythiophene)​-​graphene nanocomposite, as a highly capacitive component with a capacitance d. in the 1 mF cm-​2 range, multi-​walled carbon nanotubes, as an addnl. nanostructuring element, and a conductive org. complex, as an electron shuttle between the redox enzyme and the electrode surface. The bioanode could potentially serve as a prototype of a double-​function enzymic anode for hybrid elec. power biodevices, energizing smart contact lenses.

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)