Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ultra-thin coating traps DNA on a leash

05.12.2003


A coating that tethers DNA to a glass surface and allows the molecule to attach in three different places could make DNA microarrays denser and more affordable, according to Penn State material scientists.



DNA is the basis of enormous efforts in research and development in pharmaceutical and chemical industries across the country. To assay large numbers of DNA fragments, researchers use DNA microarrays – sometimes called biochips or genome chips. Currently, manufacture of these chips is time consuming and expensive.

Glass is the common, inexpensive substrate base for optical detection in DNA microarrays. However, the glass surface is slippery and DNA will not stick in place. Penn State researchers have developed a coating made of molecules with one side that binds to glass and the other side that grabs on to DNA strands to solve this problem.


"The coating is a single molecule thick, about one nanometer," says Dr. Carlo G. Pantano, distinguished professor of materials science and director of Penn State’s Materials Research Institute. "The DNA that attaches to this flexible leash is able to act as if it were free floating."

The organic molecules that make up the coating have one end that attaches to the glass and the other end with three functional amine groups where DNA strands can interact and attach. Retention of DNA is more than 50 percent better than found on DNA microarrays using traditional coatings.

Because fluorescent markers are routinely used with DNA microarrays to locate specific DNA fragments that have hybridized, the underlying glass and the coating need to be as non-fluorescent as possible.

Pantano, working with Samuel D. Conzone and Daniel Haines, research scientists at Schott Glass Technologies, and EzzEldin Metwalli, Penn State postdoctoral fellow, chose a variety of glasses, including pure silicon dioxide, Borofloat and flat-panel display glass, to test for self fluorescence of the glass and the coated glass. The researchers found that the coating did not change the self-fluorescence of the slide.

The researchers found that silicon dioxide glass and a Schott product called Borofloat had exceptionally low self-fluorescence. Spin coating of liquid 3-trimethoxysilylpropyl diethylenetriamine, DETA, on the surface or the glass deposited a uniform mono-molecular layer coating on the glass and did not enhance self-fluorescence. The DNA strands were then pin spotted onto the surface and the surface subsequently exposed to ultra violet light or heat so that the DNA would bind to the coating.

Tests showed that the DETA coating was better than aminopropyl triethoxysilane, a standard coating currently in use. The researchers also found that silicon dioxide based microarrays had the best retention of DNA, retaining 22.5 percent of the DNA applied and as much as 17 percent higher than other substrates tested.

"Research on coatings for DNA microarrays is driven by the need to put more spots on each slide so that more potential drugs or genes can be tested at once," says Pantano. "With less self fluorescence, better adhesion of the DNA probes, and more functionality of the tethered DNA, we are moving in the right direction. Perhaps we will find a way to produce re-usable microarrays."

Schott Glass Technologies of Duryea, Pa., who has now licensed the coating, supplied the glass used in development. Penn State has filed for a patent on this work which was supported by Schott Glass and Penn State’s National Science Foundation Materials Research Science and Engineering Center (MRSEC).

A’ndrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu/

More articles from Materials Sciences:

nachricht Less is more to produce top-notch 2D materials
20.11.2017 | The Agency for Science, Technology and Research (A*STAR)

nachricht The stacked colour sensor
16.11.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

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,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

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

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>