New materials and fabrication techniques have allowed researchers at the Hong Kong Polytechnic University(PolyU) to develop a highly permeable and superplastic conductor that can be used for the latest electronic devices.
The problem this is trying to solve
Although there have been numerous developments recently around on-skin electronics that can track hydration levels or cortisol compounds to detect stress, most of these projects have one major drawback; lack of permeability and elasticity.
Many stretchable electronics are fabricated with impermeable elastic thick films, the long-time wearing of which can cause health concerns including skin irritation and inflammation.
Moreover, low permeability limits the use of multi-layered devices, hindering the development of stretchable electronics’ advanced functionality.
- Galvanic Skin Sensor technology on wearables is just getting started
- Stanford develops a new wearable sensor to detect stress hormones
- United States Navy exploring organic nanocellulose materials for Next-Gen Wearables
How are they addressing it?
Researchers at PolyU have developed a new type of highly permeable superplastic conductor. This new conductor also called a “liquid-metal fiber mat” (LMFM), is fabricated by coating liquid metal onto an elastomeric fiber.
Not only does this new material retain superelasticity and ultrahigh conductivity, but more importantly, it has excellent biocompatibility and can be applied directly to the human skin.
Moreover, the new LMFM based material can be used to develop vertically stacked sensors. For example, you can configure one layer to serve as the ECG sensor, another for the sweat sensor, and the final layer as an electrothermal heater. The three-layer fabricated sample is only 1mm thick!!
The key takeaways
The final product is a super compatible, highly elastic, and permeable wearable sensor where sensor capabilities can be vertically stacked and applied directly to the human skin due to the product’s superior biocompatibility.
The research team at PolyU plans to enhance the performance of LMFM further and develop various types of healthcare-related electronic devices and systems.
This latest research around fabrication techniques and materials development was published in the journal Nature Materials.
Adopting this new material technology will go a long way in facilitating the development of sophisticated bio tracking systems.
There are already companies working on products that can be worn to provide health tracking. BioSleeve is a product that uses Cipher Skin’s technology to track motion and health metrics and is developing applications for physical therapy, athletic training, and more. A stretchable and more permeable sensor material that can be worn directly on the skin will boost new product developments around these use cases.