Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Organic Biosensor Detects Onset of Acute Myocardial Ischemia

Scaled-up schematic of the ion-sensitive field effect transistor that measures concentrations of potassium and hydrogen ions in the human heart.
Scaled-up schematic of the ion-sensitive field effect transistor that measures concentrations of potassium and hydrogen ions in the human heart.

Abstract:
Engineering researchers at the University of Arkansas have fabricated and tested a unique biosensor that measures concentrations of potassium and hydrogen ions in the human heart with high specificity. The research could lead to a superior method of monitoring indicators of acute myocardial ischemia, or AMI, one of the leading causes of cardiovascular failure.

Organic Biosensor Detects Onset of Acute Myocardial Ischemia

Fayetteville, AR | Posted on April 22nd, 2009

"AMI is triggered by insufficient blood supply to the heart muscles," said Taeksoo Ji, assistant professor of electrical engineering. "This lack of blood supply results in excess anaerobic metabolism, or lack of oxygen, which we know is accompanied by an increase in potassium and hydrogen ions released from cardiovascular cells. The goal is to develop a robust yet inexpensive sensor that rapidly detects these chemicals that signal the onset of AMI."

Due in part to the National Heart Lung and Blood Institute's emphasis on promoting research on rapid detection of the symptoms of acute myocardial ischemia, various types of biosensor designs, including ion-selective optical fibers, wave-guides, nanoparticle fluorescence sensors and ion-selective electrodes, have been used to detect potassium and hydrogen in the blood stream. Working in the Organic Electronics and Devices Laboratory, Ji, research assistant professor Soyoun Jung and student Pratyush Rai developed an ion-sensitive field effect transistor, yet another type of sensor used to detect potassium and hydrogen in blood.

Most ion-sensitive field effect transistors are silicon based. Instead of silicon, Ji's team worked with a low-cost organic semiconductor known as poly 3-hexylthiophene, which they fabricated on a flexible substrate. The design and fabrication process was based on special devices used to deposit organic semiconductors on substrates. Organic semiconductor films do not require high vacuum and temperature cycles for deposition and curing, which reduces cost of production.

The researchers also developed a smoothing technique to assess the effect of external electric fields on the devices. The human heart creates a great amount of electrical charge from the organ's network of neurons that help it relay electrical impulse for pace-making activity. The myocardium, or the middle section of the heart wall, has intense electrical activity. Diagnostic tools such as electrocardiograms detect electric fields emanating from the heart. To operate properly, implantable biosensor devices must be immune to these electric fields, or background noise.

The researchers' smoothing technique and noise calculation demonstrated a high signal-to-noise ratio. Overall, the testing and validation process for the device displayed stable calibration characteristics, which proved its independence from surrounding electrical fields. In other words, the sensor was immune to external voltages.

Ji collaborates with Vijay Varadan, distinguished professor of electrical engineering and director of the Center for Wireless Nano-, Bio- and Info-Tech Sensors and Systems, which is supported by the National Science Foundation. Led by Ji, the Organic Electronics and Devices Laboratory is one of the center's four laboratories.

Varadan holds the College of Engineering's Twenty-First Century Endowed Chair in Nano- and Bio-Technologies and Medicine and the college's Chair in Microelectronics and High Density Electronics. In addition to his position as director of the above center, he directs the university's High Density Electronics Center. Varadan is also a professor of neurosurgery in the College of Medicine at the University of Arkansas for Medical Sciences in Little Rock, Ark.

The researchers' findings were published in Applied Physics Letters, a journal of the American Institute of Physics Publishing. An electronic copy of the article can be provided upon request.

####

For more information, please click here

Contacts:
Matt McGowan
science and research communications officer
University Relations
479-575-4246


Taeksoo Ji
assistant professor, electrical engineering
College of Engineering
479-575-6586


Vijay Varadan
distinguished professor, electrical engineering
College of Engineering
479-575-2873

Copyright © Newswise

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.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Quantum optics allows us to abandon expensive lasers in spectroscopy: Lomonosov Moscow State University scientists have invented a new method of spectroscopy November 21st, 2017

Nano-watch has steady hands November 21st, 2017

Nano Global, Arm Collaborate on Artificial Intelligence Chip to Drive Health Revolution by Capturing and Analyzing Molecular Data in Real Time November 21st, 2017

Nanoparticles could allow for faster, better medicine: Exposure of nanoparticles in the body allows for more effective delivery November 20th, 2017

Nanomedicine

Nanoparticles could allow for faster, better medicine: Exposure of nanoparticles in the body allows for more effective delivery November 20th, 2017

Nanobiotix presented new clinical and pre-clinical data confirming NBTXR3ís significant potential role in Immuno-Oncology at SITC Annual Meeting November 14th, 2017

Arrowhead to Present at 29th Annual Piper Jaffray Healthcare Conference November 14th, 2017

A new way to mix oil and water: Condensation-based method developed at MIT could create stable nanoscale emulsions November 8th, 2017

Sensors

The stacked color sensor: True colors meet minimization November 16th, 2017

Promising sensors for submarines, mines and spacecraft: MSU scientists are developing nanostructured gas sensors that would work at room temperature November 10th, 2017

Practical superconducting nanowire single photon detector with record detection efficiency over 90 percent November 9th, 2017

Dendritic fibrous nanosilica: all-in-one nanomaterial for energy, environment and health November 4th, 2017

Discoveries

Quantum optics allows us to abandon expensive lasers in spectroscopy: Lomonosov Moscow State University scientists have invented a new method of spectroscopy November 21st, 2017

Nano-watch has steady hands November 21st, 2017

Nanoparticles could allow for faster, better medicine: Exposure of nanoparticles in the body allows for more effective delivery November 20th, 2017

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Announcements

Quantum optics allows us to abandon expensive lasers in spectroscopy: Lomonosov Moscow State University scientists have invented a new method of spectroscopy November 21st, 2017

Nano-watch has steady hands November 21st, 2017

Nano Global, Arm Collaborate on Artificial Intelligence Chip to Drive Health Revolution by Capturing and Analyzing Molecular Data in Real Time November 21st, 2017

Nanoparticles could allow for faster, better medicine: Exposure of nanoparticles in the body allows for more effective delivery November 20th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project