Featured Research

from universities, journals, and other organizations

Capturing DNA Molecules In A Nanochannel

Date:
June 27, 2008
Source:
University of Twente
Summary:
An electric voltage can be used to propel DNA molecules through a channel a few nanometers deep, or to stop them in their tracks. In a strong electric field the molecules judder along the channel, while in weaker fields they move more smoothly. This enables DNA fragments to be 'captured' on a chip and separated for analysis.

DNA molecules outside the channel have a typical ‘blob’ shape, while inside the nanochannel they have a long shape. Surface roughness and electrical field strength determine the way they move through the channel.
Credit: Image courtesy of University of Twente

An electric voltage can be used to propel DNA molecules through a channel a few nanometers deep, or to stop them in their tracks. In a strong electric field the molecules judder along the channel, while in weaker fields they move more smoothly. This enables DNA fragments to be ‘captured’ on a chip and separated for analysis.

University of Twente researchers found that, when forced through extremely shallow channels just 20 nanometers deep and a few micrometers wide, DNA molecules behave very differently than they do in free solution. In the latter situation they tend to form clumps, while molecules in the channels are forced into an elongated straitjacket. This effect alone produces a difference in mobility between long and short molecules.

Moreover, exposure to an electric field has now been shown to have a substantial effect. This presents a range of new options for the separation of fragments (and entire molecules) of DNA. The previous technique, known as gel electrophoresis, involved the use of micro-channels filled with a gel. According to researcher Georgette Salieb-Beugelaar, the laborious and time-consuming process of pouring in the gel can be rendered obsolete by the new method.

Roughness

In their Nano Letters article, the researchers ascribe the difference in mobility to factors such as the roughness of the channels’ surfaces. A DNA molecule can easily be 1000 times longer than the channels are deep.

As a result, it encounters minute surface irregularities at many different points, an effect that is reinforced by the electric field. This seems to be the cause of the stagnation in mobility that occurs in strong fields. It presents an opportunity to capture fragments and – using weaker fields - to accurately control their onward motion.

This is the first demonstration of varying mobility in electric fields of differing strengths.


Story Source:

The above story is based on materials provided by University of Twente. Note: Materials may be edited for content and length.


Journal Reference:

  1. Salieb-Beugelaar et al. Field-Dependent DNA Mobility in 20 nm High Nanoslits. Nano Letters, 2008; 0 (0): 0 DOI: 10.1021/nl080300v

Cite This Page:

University of Twente. "Capturing DNA Molecules In A Nanochannel." ScienceDaily. ScienceDaily, 27 June 2008. <www.sciencedaily.com/releases/2008/06/080624122835.htm>.
University of Twente. (2008, June 27). Capturing DNA Molecules In A Nanochannel. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2008/06/080624122835.htm
University of Twente. "Capturing DNA Molecules In A Nanochannel." ScienceDaily. www.sciencedaily.com/releases/2008/06/080624122835.htm (accessed October 20, 2014).

Share This



More Matter & Energy News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Gulfstream G500, G600 Unveiling

Gulfstream G500, G600 Unveiling

Flying (Oct. 20, 2014) Watch Gulfstream's public launch of the G500 and G600 at their headquarters in Savannah, Ga., along with a surprise unveiling of the G500, which taxied up under its own power. Video provided by Flying
Powered by NewsLook.com
Japanese Scientists Unveil Floating 3D Projection

Japanese Scientists Unveil Floating 3D Projection

Reuters - Innovations Video Online (Oct. 20, 2014) Scientists in Tokyo have demonstrated what they say is the world's first 3D projection that floats in mid air. A laser that fires a pulse up to a thousand times a second superheats molecules in the air, creating a spark which can be guided to certain points in the air to shape what the human eye perceives as an image. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
What We Know About Microsoft's Rumored Smartwatch

What We Know About Microsoft's Rumored Smartwatch

Newsy (Oct. 20, 2014) Microsoft will reportedly release a smartwatch that works across different mobile platforms, has a two-day battery life and tracks heart rate. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins