The level of stress can now be tracked as easily as steps or heart rate — directly from the hand and in real time. The device was developed by scientists from the Institute of Semiconductor Physics SB RAS (ISP SB RAS). The compact sensor is attached to the skin and analyzes the composition of sweat, showing how tense the body is.
Why the development is important
Continuous monitoring of stress levels allows you to notice dangerous conditions in time, adjust your lifestyle and maintain psycho-emotional health.
The new development is aimed at creating an inexpensive, technologically simple and easy-to-use sensor node that can be placed directly on the skin.
As indicated in the patent, the device records changes in electrical characteristics, which makes it possible to observe the state of a person in dynamics.
The main breakthrough is on the nanoscale
The key difference of the development is an ultrathin sensitive layer. Scientists used a semiconductor with a thickness of only 20 nanometers.
This is what made it possible to significantly increase the sensitivity of the sensor to cortisol. As a result, the device more accurately records changes in the concentration of substances and gives more reliable results compared to previous analogues.
How the sensor is arranged
The device is made on a flexible substrate, so it can be worn on the arm. A sensitive layer of composite electrically conductive material is applied to the substrate.
This layer includes graphene, an organic polymer and ethylene glycol. The latter reduces electrical resistance and thereby increases the sensitivity of the sensor. The layer itself can be applied by 2D printing or dropwise.
How the device reads stress
Human sweat consists of approximately 98% water and 2% chemical compounds. Among them are salts, oxygen, glucose, adrenaline, cortisol, dopamine, enzymes and other components.
When the sensor is placed on the wrist, sweat comes into contact with the sensitive layer. This leads to the accumulation of charge and an increase in electrical conductivity. It is by these changes that the device tracks the state of a person.