The high conductivity along the length makes CNTs
outstanding electrode materials. As a result, CNTs can greatly
facilitate electrochemical detection by promoting electron
transfer (McCreery, 2008) and electrodeeanalysts interactions.
They have been incorporated into electrodes via random or
aligned coating, or used as a single CNT electrode (Yang et al.,
2010b). Semiconducting CNTs can be used in nano-scale fieldeffect
transistor (Heller et al., 2008). Besides their excellent
electronic properties, the high adsorption capacity of CNTs
increases detection sensitivity (Collins et al., 2000). The major
challenge for CNT based sensors is the heterogeneity of CNTs.
Separation of metallic and semiconducting SWNT has been