Electrocardiogram (ECG) testing typically involves patches using gel and chemical adhesives. However, these patches have been criticized for their coldness, skin irritation, and signal distortion caused by movement. A gel- and adhesive-free ECG patch has been proposed, addressing these issues through structural design.

A research team led by Professor Jeong Hoon of the Department of Mechanical Engineering at UNIST announced on the 9th that they have developed a high-performance electrocardiogram patch utilizing microstructures of liquid metal and rubbery silicone. The results of the research were published in the international journal Advanced Science on January 5th.

The patch consists of a 20-micrometer-wide liquid metal tube, rolled up like a snail shell. The lower portion of the tube, where it touches the skin, is open, allowing heartbeat signals to be transmitted directly to the electrodes, enabling signal capture without the need for gel. Liquid metal leakage was addressed by inwardly curling horizontal protrusions at the bottom of the tube.

Adhesive strength comes from microscopic protrusions measuring 28㎛ in diameter and 20㎛ in height distributed across the patch's surface. These protrusions, shaped like a cap edge, adhere closely to the skin's microscopic curves, expanding the contact area and maintaining stable adhesion without adhesive. This structure ensures an adhesive strength that can withstand a weight of 100g.

Performance evaluation results showed electrode resistance was more than five times lower than that of commercial patches, and ECG signal accuracy was maintained approximately twice as high even during strenuous activities such as walking or running. Unlike conventional patches, which degrade signal quality as the gel dries, this patch ensured stable measurements even under repeated use. It can be reused more than 500 times.

The research team is transferring the technology to its joint venture, Nvix Lab, Inc., and is pursuing commercialization. The company was selected for the Ministry of SMEs and Startups' TIPS project and has already secured initial investment. The research was supported by the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, and the National Research Foundation of Korea.