Researchers at the Institute of Basic Science in South Korea have developed a highly stretchable bioelectronic mesh patch which can monitor electrophysiological signals, such as heart muscle electrical activity, and can apply electrical and thermal stimulation for therapeutic purposes. The mesh can be implanted, such as around the heart, or can be worn on the skin.
Research into new materials for wearables and implantable medical devices is proceeding rapidly. This latest study demonstrates a new material developed by Korean scientists, which can record electrical signals from tissue or skin it contacts, and deliver stimuli to the area.
The material is suited for implantation in tricky areas, such as around the heart, thanks to its potential to stretch. This ensures that it doesn’t interfere with the movement of the heart. The patch is made from gold-coated silver nanowires that are housed in a flexible rubber called polystyrene-butadiene-styrene (SBS). This gold coating acts to prevent the silver from entering the body, where it could have toxic effects, and reduces the potential for corrosion caused by bodily fluids.
“We took advantage of silver’s high conductivity, SBS’ stretchability, and gold’s high biocompatibility,” said Hyeon Taeghwan, a researcher involved in the study appearing in Nature Nanotechnology. “Finding the right proportion of each material was the key to success.”
Taeghwan and colleagues used the material to create a patch in the form of a large mesh that can fit onto the lower portion of a pig heart. The mesh can read electrical signals from the entire heart, helping to identify areas of dysfunction. For instance, the patch measured the change in ECG signal caused by an acute heart attack. The device is the first soft implant that can record electrical activity at multiple points in a pig heart.
“Although various soft cardiac devices have been reported for the rat heart, this study on pigs can approximate human physiology more accurately,” said Choi Suji, another researcher involved in the study. “We aim to study heart diseases, and stimulate the heart more effectively by synchronizing cardiac pumping activity.”
The researchers aim to assess the therapeutic potential of the patch for monitoring and treating cardiac diseases.