Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny technology leads to big changes in DNA research at Argonne

07.10.2002


New gene therapy procedures, DNA-based sensors, and other medical applications may be possible using a new method to initiate and control chemical reactions on DNA strands, developed by a team of chemists at the U.S. Department of Energy’s Argonne National Laboratory. The new technology uses specially designed nanometer-sized semiconductors--less than a billionth of an inch in size.



The technology is based on the group’s discovery of "conductive linkers"--small organic molecules that connect the electronic properties of semiconductors to biological or organic molecules. The scientists have used conductive linkers to connect strands of DNA to titanium dioxide crystals measuring only 4.5 nanometers in diameter (a nanometer is about 10,000 times narrower than a human hair).

In the presence of light, a titanium dioxide nanocrystal acts as a semiconductor, generating strong oxidizing power that attacks organic molecules in the same uncontrollable way that laundry bleach attacks all colors in the wash. The researchers found that by using different conductive linkers they can selectively control oxidation.


These nanoparticles have a wide range of potential applications in DNA-based sensing devices. The scientists use the speed of electron transfers to determine the sequence and structure of DNA strands. The four bases that make up DNA are known to have different electronic properties that vary with the sequence and structure of the DNA strand. Guanine is the most readily oxidized, and therefore has the fastest reaction. It is followed, in decreasing order of reactivity, by adenine, cytosine and thymine. By activating the titanium dioxide with light, the team can study the reactions and determine the sequence by comparing the speed and efficiency of the reactions.

The team is part of the Argonne Chemistry Division and includes Chemistry Division Director Marion Thurnauer and chemists Tijana Rajh, David Tiede and Lin Chen. In addition, the team has collaborated with Gayle Woloshak of Northwestern University, formerly of Argonne, to exploit this chemistry for use in gene therapy.

In the body, proteins called restriction enzymes are normally used to recognize and cut defective gene sequences. The researchers have created a novel "artificial restriction enzyme" that can be focused and controlled by light.

For example, a synthetic DNA single strand containing the sequence of a genetic defect can be linked to titanium dioxide. The researchers have shown that the DNA strand will carry the attached titanium dioxide to the cell nucleus, and presumably to the site of the genetic defect on the chromosome. Light will initiate the oxidative chemistry, which clips the defective gene and permits repair with a healthy gene sequence.


The nation’s first national laboratory, Argonne National Laboratory conducts basic and applied scientific research across a wide spectrum of disciplines, ranging from high-energy physics to climatology and biotechnology. Since 1990, Argonne has worked with more than 600 companies and numerous federal agencies and other organizations to help advance America’s scientific leadership and prepare the nation for the future. Argonne is operated by the University of Chicago as part of the U.S. Department of Energy’s national laboratory system.

Katie Williams | EurekAlert!
Further information:
http://www.anl.gov/

More articles from Life Sciences:

nachricht Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>