Carbon nanotube based (Bio) electronic devices

• Main Author: Liu, Ning Yi
• Other Authors: Zhang Qing
• Format: Theses and Dissertations
• Language: English
• Published: 2008
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Electronic apparatus and materials; DRNTU::Engineering::Electrical and electronic engineering::Nanoelectronics
• Online Access: https://hdl.handle.net/10356/13144
• Institution: Nanyang Technological University

Novel single-walled carbon nanotube (SWNT) based biosensors and chemical sensors for real-time detection of organophosphate and nitrylphenol compounds, respectively, have been developed. Horizontally aligned SWNTs are assembled to desirable electrodes using AC dielectrophoresis technique. For SWNT based organophosphate sensors, organophosphorus hydrolase (OPH) immobilized on the SWNTs by non-specific binding triggers enzymatic hydrolysis of organophosphates (OPs), such as paraoxon, consequently causing a detectable change in the conductance of the SWNTs. The conductance change is found to be correlated to the concentration of organophosphate. For nitrylphenol compounds detection, as-prepared CNTFETs were used. The response of the SWNT conductance was also found to be directly proportional to the concentration of nitrylphenol compound in the solution. Our results suggest that the novel biosensors and chemical sensors have great potentials to serve as a simple and reusable platform of sensing organophosphate and nitrophenol on a real-time basis. Fabrication details and detection mechanisms of these SWNT based electronic sensors are also discussed in the report. In addition, we analyzed the current fluctuation for these SWNT devices and found that 1/f noise at low frequency region plays a key role of affecting the CNT channel current.