Engineers at Tufts University in Massachusetts have integrated nano-scale sensors, electronics and microfluidics into threads that can be sutured through multiple layers of tissue to gather diagnostic data wirelessly in real time.

The development suggests that the thread-based diagnostic platform could be an effective substrate for a new generation of implantable diagnostic devices and wearable health monitors.

Threads penetrate multiple layers of tissue to sample interstitial fluid and direct it to sensing threads that collect data, such as pH and glucose levels. Image source: Tufts University School of EngineeringResearchers used a variety of conductive threads, both cotton and synthetic, that were dipped in physical and chemical sensing compounds and connected to wireless electronic circuitry. This platform was then sutured into tissue in rats as well as in vitro.

The threads were able to gather data on tissue health, such a pressure, stress, strain and temperature, as well as pH and glucose levels. Such data can be useful in determining, for example, if a wound is healing, whether infection is emerging, or whether the body's chemistry is out of balance. The results were then transmitted wirelessly to a cell phone and computer.

The three-dimensional platform is able to conform to complex structures such as organs, wounds or orthopedic implants, researchers said.

"The ability to suture a thread-based diagnostic device intimately in a tissue or organ environment in three dimensions adds a unique feature that is not available with other flexible diagnostic platforms," says Sameer Sonkusale, Ph.D., director of the interdisciplinary Nano Lab in the Department of Electrical and Computer Engineering at Tufts University's School of Engineering. "We think thread-based devices could potentially be used as smart sutures for surgical implants, smart bandages to monitor wound healing, or integrated with textile or fabric as personalized health monitors and point-of-care diagnostics."