Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NRL researchers report a forceful new method to sensitively detect proteins

18.03.2009
Scientists at the Naval Research Laboratory (NRL) recently reported the detection of toxins with unprecedented speed, sensitivity, and simplicity. The approach can sense as few as a few hundred molecules in a drop of blood in less than 10 minutes, with only four simple steps from sample to answer.

The sensitive new test builds on NRL's patent-pending Fluidic Force Discrimination™ (FFD) assay. In a FFD assay, a chip has arrays of receptor molecules such as antibodies that capture toxins or other target molecules that have been labeled with micrometer-sized beads.

By encapsulating the chip in a microflow chamber, the fluid flow can be controlled to apply just enough force to remove beads that are resting on the array but not truly labeling a toxin. "In this way," explains lead author Dr. Shawn Mulvaney, "very few molecules can be detected, because there is almost no background signal." "And because we can get the background so low," he adds, "FFD assays are very specific, with very few false positives."

In the current report, the NRL researchers have adapted FFD assays to detect a protein toxin at concentrations as low as 35 attomolar—over 1000 times more sensitive than existing commercial tests for proteins. In the new assay, dubbed "Semi-Homogeneous Fluidic Force Discrimination," the antibody-coated microbeads are mixed directly with the sample and rapidly collect the dilute toxin molecules. The toxin-coated beads are then injected into the microflow chamber where they are captured by the receptor designed for that target. Finally, beads that don't belong are removed with fluid forces. The remaining beads are all attached by the toxin to the surface and may be counted to indicate the toxin concentration. NRL has developed both electronic and optical systems to count the beads, along with reusable plastic test cartridges.

The paper won the award for Most Original Contribution at the Tenth World Congress on Biosensors, held in Shanghai, China, May 14-16, 2008 out of 978 competing papers. The awards committee noted that it was the combination of outstanding performance and modeling that set the NRL paper above the competition. The researchers developed a detailed mathematical model that includes every step of the assay, which was critical to maximizing the capture and the overall sensitivity they thereby achieved. "When very few molecules are present in a sample, such as a drop of blood," comments NRL's Dr. Paul Sheehan, "it is critical to try and capture and count every single one." Dr. Paul Sheehan emphasized that "target capture and delivery tends to be a neglected aspect of biosensor design."

"A key advantage of the NRL platform," explains Dr. Lloyd Whitman, now at the National Institute of Standards and Technology, "is that it can be applied simply even to the most challenging samples, such as serum, blood, urine, or food." "We expect it to have broad applications in medical and veterinary diagnostics, food and water testing, and national security." Dr. Mulvaney concludes, "Based on the simplicity of the method, we envision small, portable systems for point-of-care testing, field monitoring, and use by first responders."

Donna McKinney | EurekAlert!
Further information:
http://www.nrl.navy.mil

More articles from Life Sciences:

nachricht Closing the carbon loop
08.12.2016 | University of Pittsburgh

nachricht Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Closing the carbon loop

08.12.2016 | Life Sciences

Applicability of dynamic facilitation theory to binary hard disk systems

08.12.2016 | Physics and Astronomy

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D

08.12.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>