Featured Research

from universities, journals, and other organizations

Light that moves and molds gels

Date:
August 1, 2013
Source:
University of Pittsburgh
Summary:
Researchers have demonstrated a biomimetic response using hydrogels -- a material that constitutes most contact lenses and microfluidic or fluid-controlled technologies. Their study is the first to show that these gels can be both reconfigured and controlled by light, undergoing self-sustained motion -- a uniquely biomimetic behavior.

Some animals -- like the octopus and cuttlefish -- transform their shape based on environment, fending off attackers or threats in the wild. For decades, researchers have worked toward mimicking similar biological responses in non-living organisms, as it would have significant implications in the medical arena.

Now, researchers at the University of Pittsburgh have demonstrated such a biomimetic response using hydrogels -- a material that constitutes most contact lenses and microfluidic or fluid-controlled technologies. Their study, published in Advanced Functional Materials, is the first to show that these gels can be both reconfigured and controlled by light, undergoing self-sustained motion -- a uniquely biomimetic behavior.

"Imagine an apartment with a particular arrangement of rooms all in one location," said lead author Anna Balazs, Pitt Distinguished Professor of Chemical and Petroleum Engineering in the Swanson School of Engineering. "Now, consider the possibility of being able to shine a particular configuration of lights on this structure and thereby completely changing not only the entire layout, but also the location of the apartment. This is what we've demonstrated with hydrogels."

Together with Olga Kuksenok, research associate professor in the Swanson School, Balazs experimented with a newer type of hydrogel containing spirobenzopyran molecules. Such materials had been previously shown to form distinct 2-D patterns on initially flat surfaces when introduced to varying displays of light and are hydrophilic ("liking" water) in the dark but become hydrophobic ("disliking" water) under blue light illumination. Therefore, Balazs and Kuksenok anticipated that light could be a useful stimulus for tailoring the gel's shape.

Using computer modeling, the Pitt team demonstrated that the gels "ran away" when exposed to the light, exhibiting direct, sustained motion. The team also factored in heat -- combining the light and local variations in temperature to further control the samples' motions. Controlling a material with light and temperature could be applicable, Balazs said, in terms of regulating the movement of a microscopic "conveyor belt" or "elevator" in a microfluidic device.

"This theoretical modeling points toward a new way of configuring the gels into any shape, while simultaneously driving the gels to move due to the presence of light," said Kuksenok.

"Consider, for example, that you could take one sheet of hydrogel and, with the appropriate use of light, fashion it into a lens-shaped object, which could be used in optical applications," added Balazs.

The team also demonstrated that the gels could undergo dynamic reconfiguration, meaning that, with a different combination of lights, the gel could be used for another purpose. Reconfigurable systems are particularly useful because they are reusable, leading to a significant reduction in cost.

"You don't need to construct a new device for every new application," said Balazs. "By swiping light over the system in different directions, you can further control the movements of a system, further regulating the flow of materials."

Balazs said this type of dynamic reconfiguration in response to external cues is particularly advantageous in the realm of functional materials. Such processes, she said, would have a dramatic effect on manufacturing and sustainability, since the same sample could be used and reused for multiple applications.

The team will now study the effect of embedding microscopic fibers into the gel to further control the shape and response of the material to other stimuli.

Funding for this study was provided by the U.S. Department of Energy.


Story Source:

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


Journal Reference:

  1. Olga Kuksenok, Anna C. Balazs. Modeling the Photoinduced Reconfiguration and Directed Motion of Polymer Gels. Advanced Functional Materials, 2013; DOI: 10.1002/adfm.201203876

Cite This Page:

University of Pittsburgh. "Light that moves and molds gels." ScienceDaily. ScienceDaily, 1 August 2013. <www.sciencedaily.com/releases/2013/08/130801125706.htm>.
University of Pittsburgh. (2013, August 1). Light that moves and molds gels. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2013/08/130801125706.htm
University of Pittsburgh. "Light that moves and molds gels." ScienceDaily. www.sciencedaily.com/releases/2013/08/130801125706.htm (accessed July 30, 2014).

Share This




More Matter & Energy News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Climate Change Could Cost Billions, According To White House

Climate Change Could Cost Billions, According To White House

Newsy (July 29, 2014) A report from the White House warns not curbing greenhouse gas emissions could cost the U.S. billions. Video provided by Newsy
Powered by NewsLook.com
Stranded Whale Watching Boat Returns to Boston

Stranded Whale Watching Boat Returns to Boston

Reuters - US Online Video (July 29, 2014) Passengers stuck overnight on a whale watching boat return safely to Boston. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Baluchistan Mining Eyes an Uncertain Future

Baluchistan Mining Eyes an Uncertain Future

AFP (July 29, 2014) Coal mining is one of the major industries in Baluchistan but a lack of infrastructure and frequent accidents mean that the area has yet to hit its potential. Duration: 01:58 Video provided by AFP
Powered by NewsLook.com
Easier Nuclear Construction Promises Fall Short

Easier Nuclear Construction Promises Fall Short

AP (July 29, 2014) The U.S. nuclear industry started building its first new plants using prefabricated Lego-like blocks meant to save time and prevent the cost overruns that crippled the sector decades ago. So far, it's not working. (July 29) 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