Featured Research

from universities, journals, and other organizations

When Opposites Don't Attract: Understanding Why May Support New Biomaterials, Science Paper Suggests

Date:
July 20, 1999
Source:
University Of Delaware
Summary:
Every high school student is taught that opposite charges attract. Even in the complex world inside living cells, simple rules of thumb like this one usually continue to hold, and go a long way to explaining how the machinery of life all holds together. Recently, however, researchers have found an intriguing exception to this rule, which may have implications for the development of new materials for sophisticated sensors and optical devices.

Every high school student is taught that opposite charges attract. Even in the complex world inside living cells, simple rules of thumb like this one usually continue to hold, and go a long way to explaining how the machinery of life all holds together.

Related Articles


Recently, however, researchers have found an intriguing exception to this rule, which may have implications for the development of new materials for sophisticated sensors and optical devices, says Nily R. Dan, an assistant professor in UD's Department of Chemical Engineering, in a July 16 Science article.

"Our work addresses fundamental questions about how charges interact," Dan says of her joint work with researchers at the University of Pennsylvania. "In complex systems, such as multi-component materials or living cells, opposite charges don't necessarily attract. Understanding the conditions in which oppositely charged objects do or don't attract helps us understand basic strategies of self-assembly, which may be used to design new drug carriers or smart materials that respond to their environment."

Dan's article--coauthored by UD postdoctoral researcher Helim Aranda-Espinoza and by Yi Chen, Tom C. Lubensky, Philip Nelson, Laurence Ramos, and David A. Weitz of the University of Pennsylvania--examines the interactions between microscopic charged particles and oppositely charged synthetic membranes.

One would expect that the particles would adhere and cover the entire membrane surface. However, the experiments show that, frequently, only a small fraction of the membrane area is covered by adhering particles. Why do the remaining bare, oppositely charged surfaces repel particle adhesion? The researchers showed that in some cases the system prefers instead to separate into a highly adhesive zone and another, repulsive, zone by transmitting electrochemical jumps over long distances along the impenetrable membrane. While the system imitates living cells (the membrane) interacting with oppositely charged proteins (the particles), it may also be used as a model for the design of new, colloidally based materials.

Dan's research was supported by the National Science Foundation.


Story Source:

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


Cite This Page:

University Of Delaware. "When Opposites Don't Attract: Understanding Why May Support New Biomaterials, Science Paper Suggests." ScienceDaily. ScienceDaily, 20 July 1999. <www.sciencedaily.com/releases/1999/07/990720082715.htm>.
University Of Delaware. (1999, July 20). When Opposites Don't Attract: Understanding Why May Support New Biomaterials, Science Paper Suggests. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/1999/07/990720082715.htm
University Of Delaware. "When Opposites Don't Attract: Understanding Why May Support New Biomaterials, Science Paper Suggests." ScienceDaily. www.sciencedaily.com/releases/1999/07/990720082715.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
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