Carbon nanotube systems to communicate with enzymes.

The efficient transfer of electrons between enzymes and electrodes is important for understanding the intrinsic redox properties as well as for developing protein-based biosensors and bioelectronic devices. One strategy to achieve efficient electron transfer to proteins is to build up the electrode inside the protein so that it is close to the redox-active center of the protein. To achieve this requires exceedingly small electrodes. Carbon nanotubes, which are as small as 1 nm in diameter, have the potential to be such electrodes. This chapter outlines recent research toward this goal via the self-assembly of vertically aligned single-walled carbon nanotubes on electrode surfaces followed by the subsequent attachment of proteins to the free ends of the tubes.