Someday soon, a doctor may stitch a tiny piece of thread into your skin, to reveal whether a wound is healing properly or becoming infected. Researchers have developed a “smart” thread that collects and wirelessly transmits vital data.
Nano-scale sensors and electronics are infused into the thread, which can be made of cotton or synthetic material, by dipping it into a variety of physical and sensing compounds.
At some point, researchers say, the thread could be scaled up to use as sutures to close an incision on the operating table.
Either way, the information it relays would be the same, according to Sameer Sonkusale of Tufts University, and it could keep tabs on a variety of biomarkers.
“You can monitor, let’s say, glucose, which we demonstrated. You can monitor pH, you can monitor sodium and potassium ions,” said Sonkusale. “Then you have different threads that you can literally suture on a bandage, on a bandaid, or even a wound that you can place on a healthy skin and monitor your own metabolic activity. You athletes would like to monitor how well they perform. So this could also be used as a wearable sensor platform for an otherwise healthy adult.”
But Sonkusale and his electrical engineering colleagues developed the thread with wound healing in mind.
By having the “smart” thread measure pH, or the body’s chemistry balance, and temperature, doctors can tell whether an infection is brewing.
The thread can also tell physicians if a wound is healing properly, said Sonkusale. “If the tissue is healing, it has a different stretch response than if the tissue is non-healing. So you also monitor strain in the tissue,” said Sonkusale.
A paper describing the smart thread was published online in Microsystems and Nanoengineering.
‘Smart’ thread better than current monitors
Experts say the 3-D thread is a vast improvement over other biological diagnostic devices, which are flat sensors, making them difficult to use on the skin. But the smart thread is highly flexible and can be woven either outside or inside the body at the site of anything from a hip implant to an internal organ.
The researchers have attached to the thread an extremely thin wire that transmits data to a portable device. “It’s almost the width of a human hair outside the tissue," Sonkusale explained. "And there it’s connected to circuit board, a flexible circuit board which has been assembled on a fabric that wirelessly transmits that information to a cell phone. So you have real time access to biomarkers that’s inside the tissue.”
Researchers say thread is desirable because it is thin, flexible, abundant and cheap, making it perfect for collecting diagnostic information.
Sonkusale said a “smart” thread patch for athletes could be available in a year, while it will take longer for medical uses because of regulatory hurdles.