Self-repairing textile with heart rate monitoring capabilities powered by advanced technology

Scientists around the world have developed a simple metallic coating treatment for wearable clothing or textiles that can repair itself, expel bacteria from the wearer and even monitor heart signals on an electrocardiogram (ECG).

Conductive circuits created by liquid metal (LM) particles can transform wearable electronics and open doors for further development of human-machine interfaces, including soft robots and health monitoring systems, say researchers from North Carolina State University, Flinders University and South Korea.

The US team, led by the international expert in the field, Professor Michael Dickey, says that “breathable” e-textiles have special contact capabilities to “self-heal independently” even when cut.

When the coated textiles are compressed with great force, the researchers say, the particles fuse into a conductive path, enabling the creation of circuits that can maintain conductivity when stretched.

“Conductive patterns heal independently upon a cut by forming new conductive pathways along the cut edge, providing a self-healing feature that makes these textiles useful as connections between circuits, Joule heaters and flexible electrodes for measuring EKG signals,” says Flinders University Medical Researcher. In biotechnology, Dr. Khan Truong, co-senior author on a new article in the advanced materials technologies.

This technique involves dipping the coating tissue into a suspension of LM particles at room temperature.

Evenly coated textiles remain electrically insulating due to the original oxide forming on the LM particles. However, the insulating effect can be removed by compressing the fabric to rupture the oxide and thus allowing the particles to seep out.

“This allows conductive circuits to be created by compressing the tissue with a patterned mould. The electrical conductivity of the circuits is increased by covering more molecules on the tissue,” the researchers say.

In addition, LM-coated textiles provided effective antimicrobial protection against Pseudomonas aeruginosa and Staphylococcus aureus.

This ability to repel germs not only gives protective properties to the treated fabric but also prevents contamination of the breathable material if it is worn for a long time or comes into contact with other people.

Gallium-based liquid metal particles have low melting point, metallic electrical conductivity, high thermal conductivity, effectively zero vapor pressure, low toxicity and antimicrobial properties.

LM has both fluidic and metallic properties, so it shows great promise in applications such as microfluidics, soft composites, sensors, thermoswitches, and microelectronics.

One advantage of LM is that it can be deposited and patterned at room temperature on surfaces in unconventional ways that are not possible with solid metals.