Could Silly Putty stretch the possibilities of medical diagnostics?

From a child’s perspective in earlier, pre-digital times, Silly Putty was a magical plaything with an eclectic set of possibilities. Now, thanks to research conducted at Trinity College in Dublin, we can add one more application to that list: Medical diagnostics.

Researchers connected with AMBER, a materials science research center funded by Science Foundation Ireland and hosted by the historic college in the heart of Dublin, discovered that infusing the polysilicone-based toy with graphene made the material extremely sensitive to the slightest deformation or impact. Professor Jonathan Coleman and postdoctoral researcher Conor Boland of Trinity College, in collaboration with Professor Robert Young of the University of Manchester, applied the so-called G-putty to the skin of human subjects and used it to measure breathing, pulse and even blood pressure. It showed unprecedented sensitivity as a sensor for strain and pressure, hundreds of times more sensitive than normal sensors, according to the researchers, who wrote about their discovery in Science. The G-putty also works as a very sensitive impact sensor, able to detect the footsteps of small spiders. This material has the potential to enable the development of new, inexpensive devices and diagnostic instruments for medical and other applications, say the researchers.

Commenting on the discovery, Coleman said, “While a common application has been to add graphene to plastics in order to improve the electrical, mechanical, thermal or barrier properties, the resultant composites have generally performed as expected without any great surprises. The behavior we found with G-putty has not been found in any other composite material. This unique discovery will open up major possibilities in sensor manufacturing worldwide.”

The electrical resistance of graphene-infused polysilicone is very sensitive to deformation, adds Coleman, with the resistance increasing sharply under even the slightest strain or impact. “Unusually, the resistance slowly returned close to its original value as the putty self-healed over time,” he said.

Now that researchers have begun plundering toy boxes of decades past to find surprising new tools for medical technology in the 21st century, one can’t help but wonder what’s next. Silly String sutures?