Navigation Links
New sensor array detects single molecules for the first time
Date:3/7/2010

CAMBRIDGE, Mass. MIT chemical engineers have built a sensor array that, for the first time, can detect single molecules of hydrogen peroxide emanating from a single living cell.

Hydrogen peroxide has long been known to damage cells and their DNA, but scientists have recently uncovered evidence that points to a more beneficial role: it appears to act as a signaling molecule in a critical cell pathway that stimulates growth, among other functions.

When that pathway goes awry, cells can become cancerous, so understanding hydrogen peroxide's role could lead to new targets for potential cancer drugs, says Michael Strano, leader of the research team. Strano and his colleagues describe their new sensor array, which is made of carbon nanotubes, in the March 7 online edition of Nature Nanotechnology.

Strano's team used the array to study the flux of hydrogen peroxide that occurs when a common growth factor called EGF activates its target, a receptor known as EGFR, located on cell surfaces. For the first time, the team showed that hydrogen peroxide levels more than double when EGFR is activated.

EGF and other growth factors induce cells to grow or divide through a complex cascade of reactions inside the cell. It's still unclear exactly how hydrogen peroxide affects this process, but Strano speculates that it may somehow amplify the EGFR signal, reinforcing the message to the cell. Because hydrogen peroxide is a small molecule that doesn't diffuse far (about 200 nanometers), the signal would be limited to the cell where it was produced.

The team also found that in skin cancer cells, believed to have overactive EGFR activity, the hydrogen peroxide flux was 10 times greater than in normal cells. Because of that dramatic difference, Strano believes this technology could be useful in building diagnostic devices for some types of cancer.

"You could envision a small handheld device, for example, which your doctor could point at some tissue in a minimally invasive manner and tell if this pathway is corrupted," he says.

Strano points out that this is the first time an array of sensors with single-molecule specificity has ever been demonstrated. He and his colleagues derived mathematically that such an array can distinguish "near field" molecular generation from that which takes place far from the sensor surface. "Arrays of this type have the ability to distinguish, for example, if single molecules are coming from an enzyme located on the cell surface, or from deep within the cell," says Strano.

How they did it: The sensor consists of a film of carbon nanotubes embedded in collagen. Cells can grow on the collagen surface, and the collagen also attracts and traps hydrogen peroxide released by the cell. When the nanotubes come in contact with the trapped hydrogen peroxide, their fluorescence flickers. By counting the flickers, one can obtain an accurate count of the incident molecules.

Next steps: Researchers in Strano's lab plan to study different forms of the EGF receptor to better characterize the hydrogen peroxide flux and its role in cell signaling. They have already discovered that molecules of oxygen are consumed to generate the peroxide.

Strano's team is also working on carbon nanotube sensors for other molecules. The team has already successfully tested sensors for nitric oxide and ATP (the molecule that carries energy within a cell). "The list of biomolecules that we can now detect very specifically and selectively is growing rapidly," says Strano, who also points out that the ability to detect and count single molecules sets carbon nanotubes apart from many other nanosensor platforms.


'/>"/>

Contact: Jennifer Hirsch
jfhirsch@mit.edu
617-253-1682
Massachusetts Institute of Technology
Source:Eurekalert

Related biology news :

1. Louisiana Tech researchers investigate tracking, sensors to assist Air Force
2. UCLA/VA partners with ASU to advance biosensor technology for urinary tract infections
3. New microsensor measures volatile organic compounds in water and air on-site
4. New field-deployable biosensor detects avian influenza virus in minutes instead of days
5. bioMETRX, Inc. Announces Integration of AuthenTec Fingerprint Sensor in smartTOUCH(TM) Product Line
6. MIT gas sensor is tiny, quick
7. Material Technologies Holds First Electrochemical Fatigue Sensor Training for Private Inspection Firms
8. Carnegie Mellon scientists develop fluorescent proteins for live cell imaging, biosensor design
9. Atmel Receives Frost & Sullivans Technology Innovation Award for FingerChip(R) Biometric Sensor
10. New cell-based sensors sniff out danger like bloodhounds
11. New gas sensors for monitoring carbon dioxide sinks
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/19/2016)... , UAE, April 20, 2016 ... implemented as a compact web-based "all-in-one" system solution for ... biometric fingerprint reader or the door interface with integration ... modern access control systems. The minimal dimensions of the ... readers into the building installations offer considerable freedom of ...
(Date:4/13/2016)... 13, 2016  IMPOWER physicians supporting Medicaid patients in ... new clinical standard in telehealth thanks to a new ... higi platform, IMPOWER patients can routinely track key health ... mass index, and, when they opt in, share them ... to a local retail location at no cost. By ...
(Date:3/23/2016)... , March 23, 2016 ... Interesse erhöhter Sicherheit Gesichts- und Stimmerkennung mit ... Inc. (NASDAQ: MESG ), ein ... dass das Unternehmen mit SpeechPro zusammenarbeitet, um ... der Finanzdienstleistungsbranche, wird die Möglichkeit angeboten, im ...
Breaking Biology News(10 mins):
(Date:5/4/2016)... ... 04, 2016 , ... Nutrafol®, a first-to-market smart-supplement for healthy ... stress related hair loss. With patent-pending formulas for both female hair loss and ... the medical and salon channels nationwide. , Dermatologists, Plastic Surgeons and hair ...
(Date:5/3/2016)... ... May 03, 2016 , ... ... of Dr. Nancy Gillett to its Board of Directors. Dr. Gillett recently retired ... Corporate Executive Vice President and Chief Scientific Officer. A board-certified veterinary pathologist, Dr. ...
(Date:5/3/2016)... York, NY (PRWEB) , ... May 03, 2016 , ... ... Hill Hospital , for definitive prostate cancer treatment, patients traditionally had two main treatment ... appropriate treatment plan would be made. , New technology has enabled doctors to ...
(Date:5/2/2016)... ... May 02, 2016 , ... F.E.E.D. Co., the Feline ... their revolutionary, veterinarian-designed product for indoor cats. The NoBowl Feeding System replaces the ... food the way nature intended. NoBowls make cats happy and healthy. , Since ...
Breaking Biology Technology: