A new technique has been developed for creating devices out of a water-based hydrogel material. The material can be patterned, folded and used to manipulate objects.
The technique holds promise for use in "soft robotics" and biomedical applications.
"This work brings us one step closer to developing new soft robotics technologies that mimic biological systems and can work in aqueous environments," Dr. Michael Dickey, an assistant professor of chemical and biomolecular engineering at North Carolina State University and co-author of a paper describing the work said.
Dr. Orlin Velev, INVISTA Professor of Chemical and Biomolecular Engineering at NC State, the second senior author of the paper said that in the nearer term, the technique may have applications for drug delivery or tissue scaffolding and directing cell growth in three dimensions, for example.
The technique they've developed uses hydrogels, which are water-based gels composed of water and a small fraction of polymer molecules.
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.
They 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.
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.