These composites could enable development of future biosensors and biofuel cells.

Composites of glucose oxidase (GOx), carbon nanotubes (CNTs), and biologically synthesized silica have been synthesized and tested. These composites are prototypes of biological/electrical interfacial materials and could enable the development of the next generation of devices for a variety of medical, scientific, industrial, and military applications. In particular, it is envisioned that materials based on these prototypes will be integrated into bioelectrodes for biosensors and biofuel cells.

Cyclic Voltammograms of a GOx/CNT/silica-coated electrode were obtained in scans at a rate of 20 mV/s in the presence and absence of glucose at a concentration of 40 mM. The anodic and cathodic peaks shifted toward oxidative current values in the presence of glucose. This shift is attributed to a decrease, induced by enzyme activity, in the concentration of oxygen at the surface of the electrode.

GOx was chosen as the enzyme to be incorporated into the prototype composites because (1) it has been widely studied, especially with respect to DET and (2) as such, it serves as a suitable model material for the development of biosensors and fuel cells. In future development, other enzymes could be chosen to satisfy requirements in specific applications.