ANYL 297 |
| Use of carbon nanotubes in chemical and biological sensors relies on extreme sensitivity of nanotube electrical properties to local chemical environments. While mechanisms of nanotube interaction with certain small molecules appear to be understood, principles underlying interactions of more complex molecules (particularly biomolecules) with nanotubes are still unknown. Understanding of these principles is crucial for rational sensor design. We studied one of the mechanisms responsible for change in nanotube electrical response in aqueous environment – effect of local electric field of ions and charged functional groups on the nanotube transfer characteristics. Researchers often invoke this mechanism to explain nanotube-protein interactions. We changed local electric field near nanotube FETs by adsorbing polyelectrolytes and by varying surface potential of the substrate. Our results show that such purely electrostatic gating produces highly predictable, yet relatively small effect on the nanotube properties. We will discuss the implications of these findings for nanotube-based biosensor design. |
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Analytical Approaches: Sensors
8:30 AM-11:50 AM, Thursday, 14 September 2006 Moscone Center -- Room 123, Oral
Division of Analytical Chemistry |