Researchers at the University of Alabama in Huntsville have designed a wearable biosensor that provides a new way to measure human muscle activation that may prevent injury and improve athletic performance.

The design is built around a triboelectric nanogenerator (TENG), a device that converts mechanical or thermal energy into electricity for wearable electronics, and is cheaper to manufacture than traditional nanotechnology. Masu. UAH's new sensor employs an adhesive material that collects power by transferring a charge between two objects when they touch or slide against each other.

Breakthroughs are explained in detail Paper published Published in the “Journal of the Royal Society of Chemistry” co-authored with Dr. Gang Wang, Associate Professor, Faculty of Engineering. Dr. Yu Lei, Professor and Associate Professor of Chemical and Materials Engineering; Dr. Ryan Connors, Associate Professor of Kinesiology, and Dr. Moon-Hyun Jang, UAH Postdoctoral Researcher.

“Wearable biosensors provide new insights to improve human performance and well-being,” Wang said. “Our new wearable triboelectric biosensor design is composed of cellophane tape and metalized polyester sheets. When pressed and released, it can detect human movements including elbows, knees, fingers, eyes, and jaws. .

“This design is an advance because it is self-powered, lightweight, low cost, and disposable.”

Current human wearable TENG devices monitor and prevent serious body injuries in medical patients and athletes, but their manufacture requires nanotechnology expertise and expensive manufacturing methods.

“Our biosensor requires only commercially available off-the-shelf materials and a simple manufacturing scheme compared to those used for TENG-based sensors,” Wang said. “Plus, it doesn't require an external power source to function.”

Additionally, traditional devices tend to be relatively large in size compared to UAH devices, and changes in skin conditions such as sweating can reduce sensing performance, as the human skin also needs to act as a triboelectric layer. There was sex. His UAH device, which uses “sticky” materials, simplifies the design, provides a more comfortable user experience, and can detect movements that include both gross and fine movements.

“We have been using the sensor for several hours in lab tests,” Wang said. “It is very cost-effective, so new ones can be easily applied as needed. The sensors can be placed anywhere on the body where skin movements are triggered when the relevant muscles are activated. For example, different knee movements can be characterized by analyzing the collected voltage signals.We also compared the sensor's performance to an electromyography sensor in an isokinetic leg extension test.

“We are exploring opportunities to engage more subjects to conduct further testing and explore the potential for commercialization of wearable sensors. We are working with Dr. Connors’ group to develop this We are working to include more human subjects in the spring semester.”

Contraction and relaxation of the skin during body movements activates contact and separation between the polypropylene and acrylic adhesive layers. Demonstrations have been made to detect various body movements including elbow flexion, forearm supination, knee flexion/extension, proximal interphalangeal flexion/extension, eye blinking, etc.

“The patent for this device was filed in November 2023,” Wang said. “According to our experience, it takes more than a year for a patent to be granted after examination.”