A new high-performance electrocardiogram patch has been developed that eliminates the need for cold gel and chemical adhesives required by conventional ECG patches.
UNIST announced on the 10th that a research team led by Professor Jeong Hoon-eui of the Department of Mechanical Engineering developed a high-performance ECG patch that adheres easily to skin without gel or adhesive, utilizing microstructures of liquid metal and silicone rubber.
The patch features liquid metal tubes with a width of 20 micrometers (μm, where 1μm equals one-millionth of a meter) coiled in a spiral pattern resembling a snail shell. The bottom of the tubes that contact the skin are open, allowing heartbeat signals to be transmitted directly to the liquid metal electrodes. This enables effective capture of cardiac signals without gel.
While the open bottom structure could allow liquid metal to leak under pressure, the research team solved this by creating horizontal protrusions that curl inward at the bottom of the tubes. The tubes are also thin enough that the metal does not feel cold. Additionally, microscopic protrusions measuring 28μm in diameter and 20μm in height distributed across the entire patch conform seamlessly to the skin's micro-contours, eliminating the need for adhesive.
The enhanced physical adhesion reduced electrode resistance to more than five times lower than commercial patches. This means even small signals can be detected, and accurate heartbeat signals can be captured even during vigorous movement. The research team explained, "The patch adhesion is strong enough to withstand a 100-gram weight hanging from it," adding that "signal accuracy remained approximately twice as high as commercial ECG patches even during vigorous activities such as walking or running."
Unlike disposable patches used in hospitals, the new patch can be reused more than 500 times with improved durability. This is because the adhesion is generated by microstructures rather than single-use adhesive, and unlike commercial patches that lose signal accuracy when gel dries out, accurate ECG measurements are possible for extended periods without gel.
Professor Jeong Hoon-eui said, "We simultaneously solved the liquid metal leakage problem and skin adhesion issue through precise structural design alone," adding, "We expect this to serve as foundational technology for next-generation wearable systems, including long-term health monitoring technology for patients with sensitive skin and high-precision human-machine interaction interfaces."
The research team has transferred this technology to Anvixlab Inc., a company co-founded by Professor Jeong and Professor Kim Jae-jun of the Department of Electrical and Electronic Engineering, and is pursuing commercialization. The plan is to capture the next-generation wearable healthcare market with a solution combining their proprietary patch technology with on-chip AI.
The research was selected as the Inside Front Cover paper in the international journal "Advanced Science" and published on January 5th. The research was conducted with support from the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, and the National Research Foundation of Korea.