Stretchable biofuel cell with enzyme-modified conductive textiles.

A sheet-type, stretchable biofuel cell was developed by laminating three components: a bioanode textile for fructose oxidation, a hydrogel sheet containing fructose as fuel, and a gas-diffusion biocathode textile for oxygen reduction. The anode and cathode textiles were prepared by modifying carbon nanotube (CNT)-decorated stretchable textiles with fructose dehydrogenase (FDH) and bilirubin oxidase (BOD), respectively. Enzymatic reaction currents of anode and cathode textiles were stable for 30 cycles of 50% stretching, with initial loss of 20-30% in the first few cycles due to the partial breaking of the CNT network at the junction of textile fibers. The assembled laminate biofuel cell showed power of ~0.2 mW/cm(2) with 1.2 kΩ load, which was stable even at stretched, twisted, and wrapped forms.