Featured Research

from universities, journals, and other organizations

Translating language of nanopores

Date:
June 24, 2010
Source:
National Institute of Standards and Technology (NIST)
Summary:
Scientists have moved a step closer to developing the means for a rapid diagnostic blood test that can scan for thousands of disease markers and other chemical indicators of health.

Each molecule passing through the nanopore can be identified by monitoring the change it causes in an ionic current flowing across the membrane. When different molecules (purple and green objects) enter the pore (green shown in inset), each reduces the current by a certain amount and time period (shown by corresponding color scheme in the current diagram below), depending on both its size and ability to attract nearby ions (red dots). The NIST model can be used to extract this information, which might be used to identify and characterize biomarkers for medical applications.
Credit: NIST

National Institute of Standards and Technology (NIST) scientists have moved a step closer to developing the means for a rapid diagnostic blood test that can scan for thousands of disease markers and other chemical indicators of health. The team reports it has learned how to decode the electrical signals generated by a nanopore -- a "gate" less than 2 nanometers wide in an artificial cell membrane.

Nanopores are not new themselves; for more than a decade, scientists have sought to use a nanopore-based electrical detector to characterize single-stranded DNA for genetic sequencing applications. More recently, NIST scientists turned their attention to using nanopores to identify, quantify and characterize each of the more than 20,000 proteins the body produces -- a capability that would provide a snapshot of a patient's overall health at a given moment. But while nanopores permit molecules to enter into them one at a time, determining what specific individual molecule has just passed through has not been easy.

To address this problem, members of the NIST team that previously developed a method to distinguish both the size and concentration of each type of molecule the nanopore admits have now answered the question of just how these single molecules interact with the nanopore. Their new theoretical model describes the physics and chemistry of how the nanopore, in effect, parses a molecule, an understanding that will advance the use of nanopores in the medical field.

"This work brings us one step closer to realizing these nanopores as a powerful diagnostic tool for medical science," says Joseph Reiner, who performed the work with Joseph Robertson, and John Kasianowicz, all of NIST's Semiconductor Electronics Division. "It adds to the 'Rosetta Stone' that will allow us to read what molecules have just passed through a nanopore."

Using their new methods, the team was able to model the interaction of a particular type of large molecule through a nanopore's opening with great accuracy. The molecules were polyethylene glycol (PEG), a well-understood polymer that forms chains of varying length.

"PEG chains can be very long, but each link is very small," Kasianowicz says. "It was a good test because we wanted to see if the nanopore could differentiate between two nearly identical large molecules that differ in length by only a few atoms."

The team's device was able to distinguish among different-sized PEG chains easily, and the model they have developed to describe the PEG-nanopore interactions is encouraging them to think that with further effort, the minuscule sensors can be customized to measure many different molecules quickly. "We could conceivably build an array of many nanopores, each one created to measure a specific substance," Kasianowicz says. "Because each nanopore is so small, an array with one for every protein in the body would still be tiny."


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology (NIST). Note: Materials may be edited for content and length.


Journal Reference:

  1. J. E. Reiner, J. J. Kasianowicz, B. J. Nablo, J. W. F. Robertson. Theory for polymer analysis using nanopore-based single-molecule mass spectrometry. Proceedings of the National Academy of Sciences, 2010; DOI: 10.1073/pnas.1002194107

Cite This Page:

National Institute of Standards and Technology (NIST). "Translating language of nanopores." ScienceDaily. ScienceDaily, 24 June 2010. <www.sciencedaily.com/releases/2010/06/100624092528.htm>.
National Institute of Standards and Technology (NIST). (2010, June 24). Translating language of nanopores. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2010/06/100624092528.htm
National Institute of Standards and Technology (NIST). "Translating language of nanopores." ScienceDaily. www.sciencedaily.com/releases/2010/06/100624092528.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