Navigation Links
Researchers Create DNA-Based Sensors for Nano-Tongues and Nano-Noses

Nano-sized carbon tubes coated with strands of DNA can create tiny sensors with abilities to detect odors and tastes, according to researchers at the University of Pennsylvania and Monell Chemical Sciences Center. Their findings are published in the current issue of the journal Nano Letters, a publication of the American Chemical Society.

According to the researchers, arrays of these nanosensors could detect molecules on the order of one part per million, akin to finding a one-second play amid 278 hours of baseball footage or a single person in Times Square on New Years' Eve. In the report, the researchers tested the nanosensors on five different chemical odorants, including methanol and dinitrotoluene, or DNT, a common chemical that is also frequently a component of military-grade explosives. The nanosensors could sniff molecules out of the air or taste them in a liquid, suggesting applications ranging from domestic security to medical detectors.

"What we have here is a hybrid of two molecules that are extremely sensitive to outside signals: single stranded DNA, which serves as the 'detector,' and a carbon nanotube, which functions as 'transmitter,'" said A. T. Charlie Johnson, associate professor in Penn's Department of Physics and Astronomy. "Put the two together and they become an extremely versatile type of sensor, capable of finding tiny amounts of a specific molecule."

Given the size of such sensors each carbon nanotube is about a billionth of a meter wide, Johnson and his colleagues believe arrays of these sensors could serve as passive detection systems in almost any location. The sensor surface is also self-regenerating, with each sensor lasting for more than 50 exposures to the targeted substances, which means they would not need to be replaced frequently.

The specificity of single-stranded DNA is what makes these sensors so capable. These biomolecules can be engineered, in a process called directed evolution, to recognize a wide variety of targets, including small molecules and specific proteins.

Likewise, the nanotubes are ideal for signalling when the DNA has captured a target molecule. Single-walled nanotubes are formed from a single sheet of carbon molecules connected together and then rolled. It is a unique material in which every atom is on both the surface and the interior. Although nanotubes have many applications, they are extremely sensitive to electrostatic variations in their environment, whether the nanotube is in a liquid or in air.

"When the DNA portion of the nanosensor binds to a target molecule, there will be a slight change in the electric charge near the nanotube," Johnson said. "The nanotube will then pick up on that change, turning it into an electric signal that can then be reported."

According to Johnson, an array of 100 sensors with different response characteristics and an appropriate pattern recognition program would be able to identify a weak known odor in the face of a strong and variable background.

"There are few limits as to what we could build these sensors to detect, whether it is a molecule wafting off an explosive device or the protein byproduct of a cancerous growth," Johnson said.

Researchers involved in the project include Cristian Staii, a graduate student in the Department of Physics and Astronomy in Penn's School of Arts and Sciences; Michelle Chen, a graduate student in the Department of Material Science and Engineering in Penn's School of Engineering and Applied Science; and Alan Gelperin of the Monell Chemical Senses Center.

Funding for this research was provided by the U.S. Department of Energy, grants to Penn's Laboratory on the Research of the Structure of Matter through the National Science Foundation and Monell.


Source:University of Pennsylvania

Related biology news :

1. Researchers discover way to make cells in the eye sensitive to light
2. Researchers find how protein allows insects to detect and respond to pheromones
3. Researchers Uncover Key Step In Manufacture of Memory Protein
4. Researchers reveal the infectious impact of salmon farms on wild salmon
5. Researchers identify target for cancer drugs
6. Researchers discover molecule that causes secondary stroke
7. Researchers find missing genes of ancient organism
8. Researchers trace evolution to relatively simple genetic changes
9. Researchers add new tool to tumor-treatment arsenal
10. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
11. VCU Researchers Identify Networks Of Genes Responding To Alcohol In The Brain
Post Your Comments:

(Date:11/17/2015)... 2015 Pressure BioSciences, Inc. (OTCQB: PBIO) ("PBI" ... sale of broadly enabling, pressure cycling technology ("PCT")-based sample ... announced it has received gross proceeds of $745,000 from ... (the "Offering"), increasing the total amount raised to date ... closings are expected in the near future. ...
(Date:11/12/2015)...  Arxspan has entered into an agreement with ... use of its ArxLab cloud-based suite of biological ... will support the institute,s efforts to electronically manage ... internally and with external collaborators. The ArxLab suite ... Institute,s electronic laboratory notebook, compound and assay registration, ...
(Date:11/10/2015)... Nov. 10, 2015  In this report, ... basis of product, type, application, disease indication, ... this report are consumables, services, software. The ... safety biomarkers, efficacy biomarkers, and validation biomarkers. ... are diagnostics development, drug discovery and development, ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... 25, 2015 Studies reveal the ... plaque and pave the way for more effective treatment for ...     --> --> ... health problems in cats, yet relatively little was understood about ... studies have been conducted by researchers from the WALTHAM Centre ...
(Date:11/25/2015)... DIEGO , Nov. 25, 2015  Neurocrine Biosciences, ... Kevin Gorman , President and CEO of Neurocrine Biosciences, ... Healthcare Conference in New York . ... to visit the website approximately 5 minutes prior to ... A replay of the presentation will be available on ...
(Date:11/25/2015)... ... November 25, 2015 , ... ... Organization of Black Aerospace Professionals (OPBAP) has been formalized with the signing of ... team leaders met with OPBAP leaders Capt. Karl Minter and Capt. Albert Glenn ...
(Date:11/25/2015)... November 25, 2015 The ... is a professional and in-depth study on the ...      (Logo: ) , ... industry including definitions, classifications, applications and industry chain ... the international markets including development trends, competitive landscape ...
Breaking Biology Technology: