Featured Research

from universities, journals, and other organizations

New 'DNA Chip' Rapidly Detects, Identifies Dangerous Pathogens

Date:
April 15, 2003
Source:
University Of Rochester
Summary:
Detecting pathogens, whether from natural diseases or biological weapons, is about to get faster and more convenient, thanks to a new technique that can sense harmful DNA and immediately alert a doctor or scientist.

Detecting pathogens, whether from natural diseases or biological weapons, is about to get faster and more convenient, thanks to a new technique that can sense harmful DNA and immediately alert a doctor or scientist. The research, published in the April 9 issue of the Journal of the American Chemical Society, uses custom-designed loops of DNA that emit colored light in the presence of a specific creature's DNA. The loop-laden chip could be used to detect anything from a bacterium or virus, to the specific DNA of a plant or person.

"More than ever we need ways to analyze genetic material quickly, whether it's to detect an infection in a patient or identify a potentially dangerous biological substance," says Todd Krauss, assistant professor of chemistry and co-creator of the chip. "We've designed a simple method that decreases the time, cost and quite possibly the potential for error inherent in the complicated techniques used today."

The new chip is remarkable in that it eliminates many of the time-consuming steps normally taken in identifying an organism by its DNA. Traditionally, workers in a laboratory have to make thousands of copies of a piece of DNA they want to test. Then a complex series of steps must be performed to attach a special molecule to the DNA, which will act as a fluorescent beacon, making the DNA strand easy to detect. These beacon-outfitted pieces are then mixed with control DNA sequences to see if any match. Matching sequences would adhere to one another, betraying their presence via the beacon.

The Rochester team, Krauss and Benjamin Miller, associate professor of dermatology, and student Hui Du, has created a new technique that is far simpler. A scientist might only have to place a drop of the solution in question onto a small chip or card and watch for a change of color to indicate whether specific DNA is present. The chips are sensitive enough that copying may be unnecessary, as are complex beacon attachments, and the chips could be easily manufactured so doctors could instantly detect dozens or hundreds of pathogens right in their office. Future soldiers would also be able to identify unknown biological substances quickly and surely on the battlefield.

A chip using the new method would be constructed like a field of wilted sunflowers--customized sequences of DNA are bent like hairpins, with one end "planted" into a layer of metal and the other end hanging down alongside it. This dangling end contains a molecule called a flourophore, which, like the brilliant head of a sunflower, shines brightly when properly lighted. With all of the sunflowers' heads bent down to the ground, the field as a whole looks green because the fluorophore is short-circuited when directly on the metal. When "watered" with the right DNA sequence, however, the flowers stand erect, turning the entire field--and thus the chip--from green to bright yellow.

The unfolding of the chip's detector DNA strands happens when new DNA with a precise sequence is dripped onto the chip. The chip's DNA is designed to prefer to be bonded with a specific DNA sequence, such as a sequence unique to anthrax, than to remain folded over on itself. The new DNA bonds along the length of many of the chip's DNA and the two form a sort of rigid stem that lifts the beacon. The all-important beacon is pre-attached to the detector strand of DNA, rather than needing to be attached to each and every strand of DNA being tested.

Currently, the Rochester team has developed chips that can detect an antibiotic-resistant type of stalph bacteria, and they're working on chips that can detect the non-antibiotic-resistant strain as well. A laser is also needed at present to highlight the "sunflower head," but Miller and Krauss are working on ways to make the signal from the beacon more easily visible.

"We're also developing a microarray version of this chip," says Miller. "Ultimately, we'd like to design chips that could detect several different kinds of pathogens at once."

This research was funded by Evident Technologies, Inc, by the University of Rochester's Center for Future Health, and by the New York State Office of Science, Technology, and Academic Research.


Story Source:

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


Cite This Page:

University Of Rochester. "New 'DNA Chip' Rapidly Detects, Identifies Dangerous Pathogens." ScienceDaily. ScienceDaily, 15 April 2003. <www.sciencedaily.com/releases/2003/04/030415083940.htm>.
University Of Rochester. (2003, April 15). New 'DNA Chip' Rapidly Detects, Identifies Dangerous Pathogens. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2003/04/030415083940.htm
University Of Rochester. "New 'DNA Chip' Rapidly Detects, Identifies Dangerous Pathogens." ScienceDaily. www.sciencedaily.com/releases/2003/04/030415083940.htm (accessed July 28, 2014).

Share This




More Matter & Energy News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
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:
from the past week

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