Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Chemists mimic nature to design better medical tests

15.02.2012
Over their 3.8 billion years of evolution, living organisms have developed countless strategies for monitoring their surroundings.

Chemists at UC Santa Barbara and University of Rome Tor Vergata have adapted some of these strategies to improve the performance of DNA detectors. Their findings may aid efforts to build better medical diagnostics, such as improved HIV or cancer tests.

Their research is described in an article published this week in the Journal of the American Chemical Society.

Nature often serves as a source of inspiration for the development of new technologies. In the field of medical diagnostics, for example, scientists have long taken advantage of the high affinity and specificity of biomolecules such as antibodies and DNA to detect molecular markers in the blood. These molecular markers allow them to monitor health status and to guide treatments for diseases, including HIV, cancer, and diabetes.

Kevin W. Plaxco, a professor of chemistry at UCSB, whose group carried out the research, notes that despite their great attributes, a main limitation of such biosensors is their precision, which is confined to a fixed, well-defined "dynamic range" of target concentrations. Specifically, the useful dynamic range of typical biomolecule binding events spans an 81-fold range of target concentrations

"This fixed dynamic range complicates –– or even precludes –– the use of biosensors in many applications," said Plaxco. "To monitor HIV progression and provide the appropriate medication, for example, physicians need to measure the levels of viruses over five orders of magnitude. Likewise, the two orders-of-magnitude range displayed by most biosensors is too broad to precisely monitor the concentrations of the highly toxic drugs used to treat many cancers. Our goal was, therefore, to create sensors with extended (for applications needing a broad dynamic range) or narrowed (for applications needing high measurement precision) dynamic ranges at will."

The key breakthrough underlying their new approach came from the simple observation of nature. "All living organisms monitor their environments in an optimized way by using sensing molecules that respond to either wide or narrow change in target concentrations," said Alexis Vallée-Bélisle, a postdoctoral fellow and the first author of the study. "Nature does so by combining in a very elegant way multiple receptors, each displaying a different affinity for their common target".

Inspired by the optimized behaviors of these natural sensors, the UCSB research group teamed up with Francesco Ricci, professor at the University of Rome Tor Vergata to do their own mixing and matching of biomolecules to manipulate biosensors' dynamic ranges. To validate their approach, they used a widely employed DNA-based biosensor used for detecting mutations in DNA called a "molecular beacon."

By combining sets of molecular beacons all binding the same target molecule but with differing affinities, the international team was able to create sensors with rationally "tuned" dynamic ranges. In one case, they developed a sensor that monitors DNA concentrations over a six orders of magnitude range. In another example, they developed an ultrasensitive sensor that precisely detects small changes in target concentration over only a five-fold dynamic range. Finally, they also built sensors characterized by complex, "custom-made" dynamic ranges in which the sensor is insensitive within a window of desired concentrations (e.g., the clinically "normal" concentration range of a drug) and very sensitive above or below this "appropriate" concentration range. The researchers believe that these strategies can be in principle applied to a wide range of biosensors, which may significantly impact efforts to build better point-of-care biosensors for the detection of disease biomarkers.

This work was funded by the National Institute of Health, the Fond Québécois de la Recherche sur la Nature et les Technologies, the Italian Ministry of University, and Research (MIUR) project "Futuro in Ricerca."

Andrea Estrada | EurekAlert!
Further information:
http://www.ucsb.edu

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

NASA eyes Pineapple Express soaking California

24.02.2017 | Earth Sciences

New gene for atrazine resistance identified in waterhemp

24.02.2017 | Agricultural and Forestry Science

New Mechanisms of Gene Inactivation may prevent Aging and Cancer

24.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>