Polyion complex nanocomposite electrode incorporating enzyme and carbon nanotube for biofuel cells

A nanocomposite electrode of enzyme, mediator, and carbon nanotube was fabricated for the application to an enzyme electrode in biofuel cells. The nanocomposite for the anode consisted of polyion complex matrix where glucose oxidase, tetrathiafulvalene as a mediator, and carbon nanotube as an electron transport enhancer were immobilized on the glassy carbon electrode. From electrochemical measurements, the enzyme electrode possessed an ability of electro-oxidizing glucose by utilizing the enzyme activity of glucose oxidase via the redox of tetrathiafulvalene in a buffer solution (pH = 7.0) at 37 degrees C. This nanocomposite anode demonstrated a higher current density of 500 mu A cm(-1) in a glucose solution at 250 mV vs. Ag/AgCl for the application of glucose/oxygen biofuel cells.