Breathable Wearable Electronics

Breathable Wearable Electronics

A wearable device is a technology that is worn on the human body. This type of device has become a more common part of the tech world as companies have started to evolve more types of devices that are small enough to wear and that include powerful sensor technologies that can collect and deliver information about their surroundings.
The development of these wearable devices is a big challenge as they need to be in direct contact with human bodies. They might cause allergies of any kinds as well as discomfort the user. Thus a Japanese research group has developed a hypoallergenic electronic sensor that can be worn on the skin continuously for a week without discomfort and is so light and thin that users forget they even have it on. They have reported manufacturing of elastic electrode constructed of breathable nanoscale meshes shading the light on the possibility of developing noninvasive e-skin devices that can monitor a person's health continuously over a long period.
Ultrathin films and rubber sheets have been used for wearable devices for a long time; however, their lack of breathability makes them unsafe for long-term use. Some publications report that these ultrathin films and rubber sheets prevent sweating and block airflow around the skin, causing irritation and inflammation, which ultimately could lead to lasting physiological and psychological effects.

In the published paper (“Inflammation-free, gas-permeable, lightweight, stretchable on-skin electronics with nanomeshes”), the group reports that they managed to develop an electrode constructed from nanoscale meshes containing a water-soluble polymer, polyvinyl alcohol (PVA), and a gold layer. These materials are biocompatible with the human biological system and are not a source of any kinds of allergies. The device can be applied by spraying a small amount of water, which dissolves the PVA nanofibers and allows it to stick easily to the skin, it conformed seamlessly to curvilinear surfaces of human skin, such as sweat pores and the ridges of an index finger's fingerprint pattern.
 
The group reported a skin patch test on 20 participants and they have not detected any inflammation on the participants' skin after they had worn the device for a week. The group evaluated the permeability, with water vapor, of the nanomesh conductor along with those of other substrates like ultrathin plastic foil and a thin rubber sheet. They have reported that its porous mesh structure exhibited superior gas permeability compared to that of the other materials. They have also proved that the device's mechanical durability through repeated bending and stretching of a conductor attached on the forefinger exceeds 10,000 times.
This recent breakthrough reveals that soon human bodies will be covered by millions of biological sensors monitoring all body organisms; thus this breathable device can lead to a revolution in the field of wearable devices besides enhancing lives of people all over the world.