Featured Research

from universities, journals, and other organizations

Catalyst sandwich: Synthetic PCR mimic could lead to highly sensitive medical, environmental diagnostics

Date:
October 2, 2010
Source:
Northwestern University
Summary:
Researchers have taken another step towards realizing a new class of PCR enzyme mimics, opening the door for the development of highly sensitive chemical detection systems that go beyond nucleic acid targets. The blueprint for building synthetic structures to detect and signal the presence of targets such as small molecule medical analytes and environmental hazards is inspired by biology. The method also could be useful in catalysis and the production of polymers.

Northwestern University researchers have taken another step towards realizing a new class of polymerase chain reaction (PCR) enzyme mimics, opening the door for the development of highly sensitive chemical detection systems that go beyond nucleic acid targets.

The blueprint for building synthetic structures to detect and signal the presence of targets such as small molecule medical analytes (signalers of disease or bodily malfunction, such as neurotransmitters) and environmental hazards, such as TNT, to name just a few, is inspired by biology and its allosteric enzymes. The method also could be useful in catalysis and the production of polymers, including plastics.

The work, which promises higher sensitivity than that of current detection tools, will be published Oct. 1 by the journal Science.

"PCR -- the backbone of the biodiagnostics industry -- is an enzyme that binds to a nucleic acid and changes shape, turning on a catalyst that makes copies of the nucleic acid for detection purposes," said Chad A. Mirkin, George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences.

"What if you could do that for thousands of small molecules of interest?" he said. "We'd like to be able to detect tiny amounts of targets important to medicine and the environment, opening avenues to new types of diagnostic tools, just as PCR did for the modern fields of medical diagnostics and forensics. Our new catalysts could make that possible."

Mirkin led a team of chemists who built a synthetic structure that, much like the layers of an Oreo cookie, sandwiches the catalyst between two chemically inert layers. This triple-layer architecture allows the use of any catalyst as it will be kept inactive, or in an "off" state, until triggered by a specific small molecule.

The enzyme mimic behaves like allosteric enzymes found in nature, catalysts that change shape to carry out their functions. (Hemoglobin is an example of an allosteric enzyme.) When the mimic reacts with a specific small molecule, the triple-layer structure changes shape and opens, exposing the catalyst. The resulting catalytic reaction signals the presence of the small molecule target, much like PCR amplifies a single piece of DNA.

"One of our challenges as synthetic chemists has been learning to synthesize structures inspired by biology but that have nothing to do with biology other than the fact we'd like such complex functions realized in man-made systems," said Mirkin, also director of Northwestern's International Institute for Nanotechnology.

In the work reported in Science, the researchers use an aluminum salen complex as the catalyst in the three-layer structure. The addition of chloride (the reduced form of chlorine) triggers the catalyst and starts the polymerization process. (Chloride ion binds at an allosteric binding site, distant from the active or catalytic site.) The addition of an agent that removes the chloride stops the process, but the chloride can be added back to start it again.


Story Source:

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


Journal Reference:

  1. Hyo Jae Yoon, Junpei Kuwabara, Jun-Hyun Kim, and Chad A. Mirkin. Allosteric Supramolecular Triple-Layer Catalysts. Science, 1 October 2010: 66-69 DOI: 10.1126/science.1193928

Cite This Page:

Northwestern University. "Catalyst sandwich: Synthetic PCR mimic could lead to highly sensitive medical, environmental diagnostics." ScienceDaily. ScienceDaily, 2 October 2010. <www.sciencedaily.com/releases/2010/09/100930143343.htm>.
Northwestern University. (2010, October 2). Catalyst sandwich: Synthetic PCR mimic could lead to highly sensitive medical, environmental diagnostics. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2010/09/100930143343.htm
Northwestern University. "Catalyst sandwich: Synthetic PCR mimic could lead to highly sensitive medical, environmental diagnostics." ScienceDaily. www.sciencedaily.com/releases/2010/09/100930143343.htm (accessed July 25, 2014).

Share This




More Matter & Energy News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

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
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
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