Smart Mask Monitors Disease via Exhaled Breath Analysis

A person's exhaled breath – which provides information that could unveil diverse health insights – has been hard to analyze. Now, a novel "smart mask" provides real-time, non-invasive monitoring of what people exhale. The mask, dubbed EBCare, captures and analyzes exhaled breath condensate (EBC), and it offers a promising solution for continuous EBC analysis at an affordable cost. "The significance of EBCare lies in its role as a versatile, convenient, efficient, real-time research platform and solution in various medical domains, providing a robust and effective tool for this kind of future advancing clinical and medical studies," write the authors. Recent respiratory outbreaks like COVID-19 have highlighted the need for more comprehensive methods for tracking respiratory diseases. Our breath contains myriad molecular markers – from volatile organic compounds and inorganic substances to cytokines and pathogens – exhaled as gases, aerosols, or droplets. While analyzing these breath biomarkers in real-time could greatly improve the diagnoses, monitoring, and management of various respiratory and metabolic health conditions, current tools for studying EBC are severely lacking. Here, Wenzheng Heng and colleagues introduce a wearable, mechanically soft microfluidic smart mask system, designed for continuous, non-invasive analysis of EBC. Unlike traditional bulky devices that need external refrigeration to condense breath vapor, EBCare uses tandem passive cooling technologies that integrate hydrogel evaporative cooling, metamaterial radiative cooling, and a device framework with high thermal conductivity. The EBCare system enables continuous monitoring through a bioinspired microfluidic design that mimics the capillary action in plants and uses a hydrophilic inner surface to direct EBC to the sensing reservoir. Afterwards EBC is transferred to the device's outer surface, where it contributes to a continuous water source for supporting hydrogel evaporative cooling. The authors demonstrated how the mask allowed for monitoring of exhaled breath biomarkers with high accuracy, with data wirelessly transmitted via Bluetooth to a mobile app. They put it to the test through several pilot trials involving healthy individuals and patients diagnosed with chronic obstructive pulmonary disease (COPD) or asthma, and in patients after COVID-19 infection.