Vibrating carbon nanotube based bio-sensors

The potential of single-walled carbon nanotubes (SWCNTs) as a mass sensor is examined using continuum mechanics based approach. The carbon nanotube resonators are assumed to be either in cantilevered or in bridged configurations, Simple analytical formulas are developed for CNT-based nanoresonators with attached mass. A closed-form expression has been derived to detect the mass of biological objects from the frequency-shift. A simple linear approximation of the nonlinear sensor equation has been investigated. The validity and the accuracy of these formulas are examined for a wide range of cases. The results indicate that the new sensor equations can be used for CNT-based biosensors with reasonable accuracy. (C) 2009 Elsevier B.V. All rights reserved.