Home > Press > Electronic nose out in front
Abstract:
Chemical sensors are exceedingly good at detecting a single substance or a class of chemicals, even at highly rarified concentrations. Biological noses, however, are vastly more versatile and capable of discriminating subtle cues that would confound their engineered counterparts. Unfortunately, even highly trained noses do leave a certain ambiguity when relaying a signal and are not particularly suited for work in specialized situations like operating rooms. A new DNA-based chemical sensor appears to be both extremely sensitive and discerning, making it an important stride on the path to an all-electronic nose.
A team of researchers report in a paper published in the American Institute of Physics' journal AIP Advances that specially tailored strands of DNA attached to carbon nanotubes can tell the difference between very similar molecules, even those that have an identical chemical makeup. "We're trying to develop this into an electronic nose system," says A.T. Charlie Johnson, a physicist at the University of Pennsylvania and study co-author. "We used this system to distinguish between optical isomers, molecules that are nearly identical except that one is structurally reversed - a mirror image."
The system works by affixing DNA strands to carbon nanotubes, which are excellent electrical conductors. The DNA strands have been fine-tuned to respond to particular chemicals, so when strands come in contact with a target chemical - even at very low concentrations - it produces a measurable electrical signal along the nanotube. The sensors were able to check for molecules that differ by as little as one carbon atom. Though the researchers are not the first to observe this effect, they have achieved an unprecedented level of differentiation for an all-electronic chemical detector. "What I'm focusing on is the size of the difference in the signal," says Johnson.
The researchers are next interested in creating something akin to an actual electronic nose consisting of many individual DNA-based sensors performing the same role as an olfactory receptor. The goal is to have a system that is highly versatile and sensitive with wide-scale applications. For example, the chemical dimethylsulfone is associated with skin cancer. The human nose cannot detect this volatile but it could be detected with the new sensor at concentrations as low as 25 parts per billion.
Acknowledgements: This work was supported by the Army Research Office and by the Nano/Bio Interface Center through the National Science Foundation.
Article: "DNA-decorated carbon nanotube-based FETs as ultrasensitive chemical sensors: Discrimination of homologues, structural isomers, and optical isomers" is published in AIP Advances.
Authors: S.M. Khamis (1), R.A. Jones (1), A.T. Charlie Johnson (1), G. Preti (2,3), J. Kwak (2), and A. Gelperin (2,4).
(1) Department of Physics and Astronomy, University of Pennsylvania, Philadelphia
(2) Monell Chemical Senses Center, Philadelphia
(3) Department of Dermatology, University of Pennsylvania
(4) Princeton Neuroscience Institute, Princeton University, New Jersey
####
For more information, please click here
Contacts:
Charles Blue
301-209-3091
Copyright © American Institute of Physics
If you have a comment, please Contact us.Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
Related News Press |
News and information
Simulating magnetization in a Heisenberg quantum spin chain April 5th, 2024
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Govt.-Legislation/Regulation/Funding/Policy
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Chemical reactions can scramble quantum information as well as black holes April 5th, 2024
Nanotubes/Buckyballs/Fullerenes/Nanorods/Nanostrings
Tests find no free-standing nanotubes released from tire tread wear September 8th, 2023
Detection of bacteria and viruses with fluorescent nanotubes July 21st, 2023
Sensors
Discoveries
Chemical reactions can scramble quantum information as well as black holes April 5th, 2024
New micromaterial releases nanoparticles that selectively destroy cancer cells April 5th, 2024
Utilizing palladium for addressing contact issues of buried oxide thin film transistors April 5th, 2024
Announcements
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Military
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024
New chip opens door to AI computing at light speed February 16th, 2024
The latest news from around the world, FREE | ||
Premium Products | ||
Only the news you want to read!
Learn More |
||
Full-service, expert consulting
Learn More |
||