This $1 Smart Mask Cools Your Breath to Capture Condensates — and Analyzes It in Real-Time

Researchers from the California Institute of Technology (Caltech) and the Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center have developed a face mask that helps you keep your cool — while also sampling your breath for health monitoring and disease diagnosis.

"Monitoring a patient's breath is something that is routinely done, for example, to assess asthma and other respiratory conditions. However, this has required the patient to visit a clinic for sample collection, followed by a waiting period for lab results," explains lead investigator Wei Gao. "Since COVID-19, people are wearing masks more. We can leverage this increased mask use for remote personalized monitoring to get real-time feedback about our own health in our home or office. For instance, we could use this information to assess how well a medical treatment may be working."

The base of the team's smart mask, dubbed EBCare, is an off-the-shelf disposable N95 mask. Rather than use it as-is, though, the team used a laser cutter to punch a hole through the material — in order to mount an adapter, created using 3D-printed molds, for a system which uses a hydrogel-based cooling system to cool and condense liquid from the wearer's breath and capture it for analysis by on-mask sensors, transporting it through microfluidic channels inspired by plants.

"The mask represents a new paradigm for respiratory and metabolic disease management and precise medicine because we can easily get breath specimens and analyze the chemical molecules in breath in real time through daily masks," claims lead author Wenzheng Heng. "The breath condensate contains soluble gases as well as non-volatile substances in the form of aerosols or droplets, such as metabolic substances, inflammatory indicators, and pathogens."

In testing, the mask assembly proved able to monitor wearers' breath for nitrite — a biomarker indicating inflammation, commonly found in patients with asthma or chronic obstructive pulmonary disorder (COPD). In another test, different sensors were added to monitor the wearer's blood alcohol concentration — and in the team's latest experiments yet another sensor was added to look for ammonium, which is indicative of high urea concentrations caused by kidney disease.

"These first studies are a proof of concept," Gao 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. The smart mask can be prepared at a relatively low cost. It is designed to cost only about $1 in materials."

The team's work has been published in the journal Science under closed-access terms.