Featured Research

from universities, journals, and other organizations

'Soft robotic' devices using water-based gels

Date:
August 2, 2013
Source:
North Carolina State University
Summary:
Researchers have developed a new technique for creating devices out of a water-based hydrogel material that can be patterned, folded and used to manipulate objects. The technique holds promise for use in "soft robotics" and biomedical applications.

The hydrogel “grabber” can grasp and release objects.
Credit: Orlin Velev

Researchers from North Carolina State University have developed a new technique for creating devices out of a water-based hydrogel material that can be patterned, folded and used to manipulate objects. The technique holds promise for use in "soft robotics" and biomedical applications.

Related Articles


"This work brings us one step closer to developing new soft robotics technologies that mimic biological systems and can work in aqueous environments," says Dr. Michael Dickey, an assistant professor of chemical and biomolecular engineering at NC State and co-author of a paper describing the work.

"In the nearer term, the technique may have applications for drug delivery or tissue scaffolding and directing cell growth in three dimensions, for example," says Dr. Orlin Velev, INVISTA Professor of Chemical and Biomolecular Engineering at NC State, the second senior author of the paper.

The technique they've developed uses hydrogels, which are water-based gels composed of water and a small fraction of polymer molecules. Hydrogels are elastic, translucent and -- in theory -- biocompatible. The researchers found a way to modify and pattern sections of hydrogel electrically by using a copper electrode to inject positively charged copper ions into the material. Those ions bond with negatively charged sites on the polymer network in the hydrogel, essentially linking the polymer molecules to each other and making the material stiffer and more resilient. The researchers can target specific areas with the electrodes to create a framework of stiffened material within the hydrogel. The resulting patterns of ions are stable for months in water.

"The bonds between the biopolymer molecules and the copper ions also pull the molecular strands closer together, causing the hydrogel to bend or flex," Velev says. "And the more copper ions we inject into the hydrogel by flowing current through the electrodes, the further it bends."

The researchers were able to take advantage of the increased stiffness and bending behavior in patterned sections to make the hydrogel manipulate objects. For example, the researchers created a V-shaped segment of hydrogel. When copper ions were injected into the bottom of the V, the hydrogel flexed -- closing on an object as if the hydrogel were a pair of soft tweezers. By injecting ions into the back side of the hydrogel, the tweezers opened -- releasing the object.

The researchers also created a chemically actuated "grabber" out of an X-shaped segment of hydrogel with a patterned framework on the back of the X. When the hydrogel was immersed in ethanol, the non-patterned hydrogel shrank. But because the patterned framework was stiffer than the surrounding hydrogel, the X closed like the petals of a flower, grasping an object. When the X-shaped structure was placed in water, the hydrogel expanded, allowing the "petals" to unfold and release the object.

"We are currently planning to use this technique to develop motile, biologically compatible microdevices," Velev says.

"It's also worth noting that this technique works with ions other than copper, such as calcium, which are biologically relevant," Dickey says.

The paper, "Reversible patterning and actuation of hydrogels by electrically assisted ionoprinting," was published online Aug. 2 in Nature Communications. Lead authors of the paper are Dr. Etienne Palleau, a former postdoctoral researcher at NC State, and Daniel Morales, a Ph.D. student at NC State. The work was supported by the National Science Foundation's Research Triangle Materials Research Science and Engineering Center and DS/DGA-France.

In 2011, Velev and Dickey published research on their development of gel-like memory devices that function in wet environments.

Video: http://www.youtube.com/watch?v=9SXWJP1KK-8&feature=youtu.be


Story Source:

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


Journal Reference:

  1. Etienne Palleau, Daniel Morales, Michael D. Dickey, Orlin D. Velev. Reversible patterning and actuation of hydrogels by electrically assisted ionoprinting. Nature Communications, 2013; 4 DOI: 10.1038/ncomms3257

Cite This Page:

North Carolina State University. "'Soft robotic' devices using water-based gels." ScienceDaily. ScienceDaily, 2 August 2013. <www.sciencedaily.com/releases/2013/08/130802080345.htm>.
North Carolina State University. (2013, August 2). 'Soft robotic' devices using water-based gels. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2013/08/130802080345.htm
North Carolina State University. "'Soft robotic' devices using water-based gels." ScienceDaily. www.sciencedaily.com/releases/2013/08/130802080345.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NASA's First 3-D Printer In Space Creates Its First Object

NASA's First 3-D Printer In Space Creates Its First Object

Newsy (Nov. 26, 2014) The International Space Station is now using a proof-of-concept 3D printer to test additive printing in a weightless, isolated environment. Video provided by Newsy
Powered by NewsLook.com
Bolivian Recycling Initiative Turns Plastic Waste Into School Furniture

Bolivian Recycling Initiative Turns Plastic Waste Into School Furniture

Reuters - Innovations Video Online (Nov. 26, 2014) Innovative recycling project in La Paz separates city waste and converts plastic garbage into school furniture made from 'plastiwood'. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Who Will Failed Nuclear Talks Hurt Most?

Who Will Failed Nuclear Talks Hurt Most?

Reuters - Business Video Online (Nov. 25, 2014) With no immediate prospect of sanctions relief for Iran, and no solid progress in negotiations with the West over the country's nuclear programme, Ciara Lee asks why talks have still not produced results and what a resolution would mean for both parties. Video provided by Reuters
Powered by NewsLook.com
Flying Enthusiast Converts Real-Life Aircraft Cockpit Into Simulator

Flying Enthusiast Converts Real-Life Aircraft Cockpit Into Simulator

Reuters - Innovations Video Online (Nov. 25, 2014) A virtual flying enthusiast converts parts of a written-off Airbus aircraft into a working flight simulator in his northern Slovenian home. Jim Drury 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