A research team at the Center for Nanoparticle Research, within the Institute for Basic Science (IBS), has developed a wearable and implantable device that measures electrophysiological signals and applies electrical and thermal stimulations.
The new soft Bioelectronic Mesh offers information on muscle and cardiac dysfunctions, and thus could be implemented for pain relief, rehabilitation, and prosthetic motor control.
This new device was used by researchers on human skin to record the electrical activity of heart and muscles, that is electrocardiogram (ECG) and electromyogram (EMG) respectively.
Due to its softness, elasticity and stretchability, it can follow the contours of flexible joints, such as the wrist.
When worn on a forearm, it simultaneously monitors EMG signals and delivers electrical and/or thermal stimulations that could be employed in therapeutic applications.
Researchers have also produced a customised large mesh that fits the lower part of a swine heart.
When wrapped around the heart, this implant can study signals from the complete organ to identify possible lesions and help recovery.
The mesh is also stable during heart movements and does not interfere with the heart’s pumping activity.
First co-author of the study Choi Suji said: “Although various soft cardiac devices have been reported for the rat heart. This study on pigs can approximate human physiology more accurately.
“We aim to study heart diseases, and stimulate the heart more effectively by synchronizing cardiac pumping activity.”
The patch, which is stretchable and conductive, is made by gold-coated silver nanowires mixed with a kind of rubber, called polystyrene-butadiene-styrene (SBS).
Regular silver wire-based conductive rubbers have had limited biomedical applications as silver is harmful to the body.
For this study, the gold sheath avoids both silver’s leaching, and corrosion caused by air and biological fluids, such as sweat.
The centre’s director and co-author Hyeon Taeghwan said: “We took advantage of silver’s high conductivity, SBS’ stretchability, and gold’s high biocompatibility.
“Finding the right proportion of each material was the key to success.”