Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sensor gives valuable data for neurological diseases and treatments

20.04.2010
A new biosensor developed at Purdue University can measure whether neurons are performing correctly when communicating with each other, giving researchers a tool to test the effectiveness of new epilepsy or seizure treatments.

Marshall Porterfield, an associate professor of agricultural and biological engineering and biomedical engineering, postdoctoral researcher Eric McLamore, and graduate student Subhashree Mohanty developed the self-referencing glutamate biosensor to measure real-time glutamate flux of neural cells in a living organism. The nanosensor not only measures glutamate around neural cells, it can tell how those cells are releasing or taking up glutamate, a key to those cells' health and activity.

"Before we did this, people were only getting at glutamate indirectly or through huge, invasive probes," said Porterfield, whose research was published in the early online version of the Journal of Neuroscience Methods. "With this sensor, we can 'listen' to glutamate signaling from the cells."

The firing of neurons is involved in every action or movement in a human body. Neurons work electrically, but ultimately communicate with each other through chemical neurotransmitters such as glutamate. One neuron will release glutamate to convey information to the next neuron's cell receptors.

Once the message is delivered, neurons are supposed to reabsorb or clear out the glutamate signal. It is believed that when neurons release too much or too little glutamate and are not able to clear it properly, people are prone to neurological diseases.

Jenna Rickus, an associate professor of agricultural and biological engineering and biomedical engineering who oversaw the study's neurological aspects, said researchers need more information about how neurons work to create more effective treatments for neurological disorders.

"Understanding neurotransmitter dynamics has implications for almost all normal and pathological brain function," Rickus said. "The reason we don't have good information is because we haven't had a good measurement tool before."

Porterfield and McLamore's sensor exploits conductive carbon nanotubes and is only 2 micrometers in diameter, or about 50 times smaller than the diameter of a human hair. They also use an enzyme, called glutamate oxidase, on the end of the probe that reacts with glutamate to create hydrogen peroxide. The carbon nanotubes enhance the conductivity of the hydrogen peroxide, and a computer can calculate the movement of glutamate relative to the cell surface.

The sensor oscillates and samples the concentration activities of glutamate at various positions relative to the neurons in culture. Those measurements at different distances can tell researchers whether the glutamate is flowing back toward the neurons or dissipating in many directions.

Current sensor technology allows for sensing in vitro, but those probes are large and invasive, Porterfield said, and they don't measure the movement of the chemicals.

McLamore said the sensor also is valuable because it is able to hone in on only glutamate using just one probe and custom software that filters out variations in the signals that are read, which removes signal noise due to other compounds.

"There are many compounds present near the neurons which can potentially create noise, but this sensor should be selective for one compound. We filter out all of the background noise," McLamore said. "It's the same thing modern hearing aids do. They're filtering out ambient noises, and that's the same thing you get when you oscillate a biosensor."

The sensor also could be adapted to measure other chemicals by changing the enzyme used on its tip.

Rickus said the sensor's versatility would be valuable for understanding the effects of therapies for epilepsy, Parkinson's disease, damage caused by chemotherapy, memory loss and many other conditions. The sensor will give valuable data on how damaged neurons function and how drugs or therapies affect those cells.

Porterfield said the next step is to make small improvements to the sensor and adapt it to use other enzymes. The Office of Naval Research funded the research.

Writer: Brian Wallheimer, 765-496-2050, bwallhei@purdue.edu

Sources: Marshall Porterfield, 765-494-1190, porterf@purdue.edu
Jenna Rickus, 765-494-1197, rickus@purdue.edu
Eric McLamore, 806-239-9556, emclamor@purdue.edu

Brian Wallheimer | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>