Many people still wear masks on a regular basis, either to keep from spreading viruses that they've got, or to manage a respiratory problem. An experimental new mask takes things a step further, by analyzing its wearer's breath to check their state of health.
Created by Prof. Wei Gao and colleagues at the California Institute of Technology, the EBCare (Exhaled Breath Condensate) mask is designed to monitor respiratory ailments including COPD (chronic obstructive pulmonary disease), asthma, and post-COVID-19 infections. That said, it could have a number of additional uses.
Unlike some other health-monitoring "smart masks," it does not track characteristics such as the rate, temperature or humidity of the wearer's breath. Instead, it focuses on identifying telltale chemicals within their exhalations, providing readings on the levels of those biomarkers.
As the user exhales, their moist breath is cooled via an integrated system which combines evaporative cooling (in the form of a hydrogel) with radiative cooling. As a result, the water droplets in their breath condense into liquid form.
That liquid is then drawn into a series of microfluidic channels via capillary action, which carry it down to a reservoir. Sensors in that reservoir then analyze the liquid, each one set to detect a certain chemical. The sensory data is wirelessly transmitted to an app on the wearer's smartphone, which displays the results in real time.
In tests performed on patients with asthma and COPD, the EBCare mask accurately detected levels of exhaled nitrite, which is a compound associated with inflammation of the airways. It was also successful at measuring levels of exhaled ammonium, which correspond to urea levels in the blood – high levels of urea in the bloodstream are in turn an indicator of kidney problems.
The mask was even able to accurately measure blood alcohol levels via alcohol in the breath, suggesting that it could be used as a cheaper alternative to electronic breathalyzers. Gao states that the device is designed to cost only about one dollar in materials, if manufactured on a commercial scale.
"These first studies are a proof of concept," he says. "We want to expand this technology to incorporate different markers related to various health conditions. This is a foundation for creating a mask that functions as a versatile general health-monitoring platform."
A paper on the research was recently published in the journal Science.
Source: Caltech
