Research Teams Advance Sensing Capabilities of Carbon Nanotubes

TEMPE, AZ /PRNewswire-FirstCall/ -- Motorola Labs, the applied research arm of Motorola Inc., and Arizona State University (ASU) announce a key advancement in the use of single-walled carbon nanotubes (SWNTs) in field effect transistors (FETs) to sense biological and chemical agents. Together, the research teams have developed a method to functionalize SWNTs with peptides to produce low-power SWNT-FETs that are highly sensitive and can selectively detect heavy metal ions down to the parts-per-trillion level.

"Integration of nanosensors into devices and sensor networks will enable the detection of biological and chemical agents at very low concentrations, which could be vital in the areas of public safety and homeland security," said Vida Ilderem, vice president of Embedded Systems Research Labs in Tempe, AZ. "In the future, these sensors could be integrated into devices to produce a powerful network that can seamlessly communicate environmental changes to people or other devices."

Researchers have successfully tuned SWNT-FETs to sense specific agents by applying a peptide-functionalized polymer coating that does not affect their ability to transmit electrical signals. This developing sensor technology could be used to monitor a host of environmental and health issues, including air and water quality, industrial chemicals, and biological agents.

"Our sensor is based on the unique properties of peptides and carbon nanotubes. Peptides can be used to recognize and detect various chemical species with astonishing sensitivity and selectivity while carbon nanotubes are known for their unique electronic properties," said Nongjian Tao, a professor in the department of electrical engineering in ASU's Ira A. Fulton School of Engineering. "The combination of the two allows us to quickly convert the recognition events of the peptides into an electronic signal."

This work is reported in a paper coauthored by Arizona State University and Motorola titled "Tuning the Chemical Selectivity of SWNT-FETs for Detection of Heavy-Metal Ions," which will be published in the journal Small. An early view of the article is available on the journal's Web site.

Researchers will now investigate the sensing of other analytes and the feasibility of multi-analyte detection with selective sensing libraries.

About Motorola
Motorola is known around the world for innovation and leadership in wireless and broadband communications. Inspired by our vision of seamless mobility, the people of Motorola are committed to helping you get and stay connected simply and seamlessly to the people, information, and entertainment that you want and need. We do this by designing and delivering "must have" products, "must do" experiences, and powerful networks—along with a full complement of support services. A Fortune 100 company with global presence and impact, Motorola had sales of $35.3 billion in 2005. For more information about our company, our people, and our innovations, please visit our Web site.

About Arizona State University
Arizona State University (ASU) is among the premier public research universities in the nation. More than 60,000 undergraduate, graduate, and professional students are enrolled on the university's four campuses in the metropolitan Phoenix area. ASU offers numerous resources for study and research, including state-of-the-art laboratories and other facilities for science and technology innovation, as well as libraries, museums, and performing arts spaces. ASU's Ira A. Fulton School of Engineering is ranked nationally in the top 50 among more than 185 engineering schools rated by US News & World Report magazine. Its 200-plus faculty members pursue research in electrical, chemical, materials, mechanical, aerospace, civil and environmental engineering, bioengineering, and computer science.