Featured Research

from universities, journals, and other organizations

Sensor Uses DNA To Detect Presence Of Lead, A Dangerous Contaminant

Date:
November 7, 2000
Source:
University Of Illinois At Urbana-Champaign
Summary:
Lead is a common environmental contaminant that can cause a number of health problems, particularly in children. Current techniques for lead detection require sophisticated equipment or complicated sample treatment. Now, researchers at the University of Illinois have developed a simple and inexpensive method that permits real-time, on-site detection of lead ions.

CHAMPAIGN, Ill. — Lead is a common environmental contaminant that can cause a number of health problems, particularly in children. Current techniques for lead detection require sophisticated equipment or complicated sample treatment. Now, researchers at the University of Illinois have developed a simple and inexpensive method that permits real-time, on-site detection of lead ions.

“A unique feature of our lead sensors is that they consist of small pieces of DNA, the same basic building block of our genes,” said Yi Lu, a UI professor of chemistry. DNA is a well-known genetic material with different combinations of “code” or sequences that determine individual characteristics such as eye color, hair color and height.

“This represents a new class of simple and environmentally safe sensors and is the first example of a catalytic DNA-based biosensor for metal ions,” Lu said. “It combines the high metal ion selectivity of catalytic DNA with the high sensitivity of fluorescence detection.”

Because DNA is stable, cost-effective and easily adaptable to optical fiber and chip technology, the catalytic DNA system is an ideal candidate for real-time, remote sensing of lead in applications such as environmental monitoring, clinical toxicology and industrial process monitoring.

To search for the unique sequence of DNA that could distinguish lead from other metal ions, Lu and graduate student Jing Li used a method called in vitro selection. The selection process is capable of sampling a very large pool of DNA sequences (up to 1000 trillion molecules), amplifying the desired sequences by the polymerase chain reaction and introducing mutations to improve performance.

Using in vitro selection, Lu and Li found several DNA sequences that were especially responsive to the presence of lead ions. To enhance the sensitivity of the sensor, the researchers attached a fluorescent tag to a specific DNA sequence.

While most DNA is double stranded, the catalytic DNA Lu and Li selected has a single strand that can wrap around like a protein. In that single strand, the researchers fashion a specific binding site – a kind of pocket that can only accommodate the metal ion of choice.

“The principles demonstrated in this work can also be used to obtain DNA biosensors for other metal ions that are toxic (such as mercury and cadmium) or beneficial (such as calcium and potassium) to humans,” Lu said. “At the same time, we can offer insight into both the sequence and structure of DNA that is responsible for the metal specificity.”

Lu and Li described their catalytic DNA sensor in the Oct. 25 issue of the Journal of the American Chemical Society. Funding was provided by the National Institutes of Health. The researchers have applied for a patent.


Story Source:

The above story is based on materials provided by University Of Illinois At Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University Of Illinois At Urbana-Champaign. "Sensor Uses DNA To Detect Presence Of Lead, A Dangerous Contaminant." ScienceDaily. ScienceDaily, 7 November 2000. <www.sciencedaily.com/releases/2000/11/001106060504.htm>.
University Of Illinois At Urbana-Champaign. (2000, November 7). Sensor Uses DNA To Detect Presence Of Lead, A Dangerous Contaminant. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2000/11/001106060504.htm
University Of Illinois At Urbana-Champaign. "Sensor Uses DNA To Detect Presence Of Lead, A Dangerous Contaminant." ScienceDaily. www.sciencedaily.com/releases/2000/11/001106060504.htm (accessed October 21, 2014).

Share This



More Matter & Energy News

Tuesday, October 21, 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