just a piece of paper.

Exploiting a natural substance that is in abundance, such as paper, creates an affordable, disposable and accessible sensing solution.

Paper adsorbs water.

adsorb [verb]

To cause a substance, usually gas, to form a very thin layer on the surface of another substance.

As water is deposited onto the paper from breathing, a thin film of water builds on the surface of the cellulose fibers, which causes the conductivity between the carbon electrodes to increase.


When you breathe in, water is removed from the film layer and causes the conductivity to decrease.

This cyclic change gives the ability to watch breathing pattern in near real time.

Paper based sensor to help identify seps

Did you know?

In an environment that has 50% relative humidity, 5% of paper's weight will be water.

Relative humidity [noun]

The amount of water that is present in the air compared to the greatest amount it would be possible for the air to hold at that temperature.

Sensors to detect Disease.

Modifying the inks and substrate layers has given rise to the ability to sense compounds and gases on breath for non-invasive diagnostic solutions.

As Spyras continues to grow, innovate and research into new applications for breath-based sensors, we will share our findings and results on our research pages.