Shape-shifting gels that move help Pitt researchers take fiction out of science
Shape-shifting gels that run away from light might sound like science fiction, but University of Pittsburgh researchers say computer models suggest fiction is morphing into fact.
Anna Balazs, a professor of chemical and petroleum engineering, and Olga Kuksenok, an engineering research professor at Pitt, said they looked to nature for inspiration when working with hydrogels — compounds widely used in contact lenses, membranes, glue and medical testing devices that rely on fluid technologies.
They wanted to find out whether a man-made product could mirror behavior seen in the mimic octopus, a shape-shifting ocean creature that can imitate the shape, color and texture of at least 15 creatures ranging from the lionfish to sea floor algae.
Such actions long have been a holy grail for researchers.
“Overall we are very interested in designing materials that mimic biology,” Balazs said.
Josianne Romasco, aquarist keeper at the Pittsburgh Zoo & PPG Aquarium, isn't surprised that researchers looked to an octopus for inspiration. Although the zoo doesn't house a mimic octopus, it has octopi with varying abilities.
“Roboticists have come here to study them. And with their ability to change color and camouflage themselves, they're just very interesting creatures,” Romasco said.
Creating manufactured materials that could mimic such a response to external stimuli could have wide-ranging implications for everything from soft robotics to medical testing devices, Balazs said.
For the octopus, the ability to mimic its surroundings is a matter of surviving threats from predators and thriving in a sometimes hostile sea. For manufactured products, Balazs said it could mean repurposing materials and reducing production costs.
She and Kuksenok collaborated on a two-year study of hydrogels and recently published the results in the journal, Advanced Functional Materials.
Their study tapped physics, chemistry, biology and computational science, using computer models to examine the behavior of a hydrogel first made in 2007.
“The gels we were looking at were in the micron to millimeter scale,” Balazs said. “When you move the light over them from left to right, and take several swipes over them, they shrink and move in the direction opposite the light.”
The finding, she said, suggests new ways of shaping and molding gels.
Kuksenok and Balazs also found that by using different lights, they could reconfigure gels for another use. That quality could reduce manufacturing costs, Balazs said.
Debra Erdley is a Trib Total Media staff writer. Reach her at 412-320-7996 or firstname.lastname@example.org.