The Effect of Network Density on the DNA-Sensing Performance of Single-Walled Carbon Nanotubes

Abstract

The effect of network density of single-walled carbon nanotubes (SWNTs) on the detection of DNA hybridization was investigated. The results show that, in contrast to those having higher densities, SWNTs with low network densities in the conductance range of 0.74 x 10(-7) < G(bare) < 2.00 x 10(-7) exhibit high sensitivity for detection of immobilized DNAs. The resulting SWNT devices with optimal network densities showed good selectivity in detecting cDNA hybridization. The network density control will provide opportunities to realize practical label free biosensor utilizing commercially available SWNT networks.