Smart Wearable Devices for Exhaled Breath Condensate Harvesting and Health Monitoring

Exhaled breath condensate (EBC), a non-invasive biofluid that captures biomarkers (small molecules, proteins, nucleic acids) from airway surface fluid, offers novel avenues for pathophysiological research and clinical management of respiratory and systemic diseases. Despite advancements in sample collection and detection, clinical translation remains hindered by critical challenges: inconsistent biomarker standardization leads to cross-study data variability, and the absence of miniaturized equipment limits real-time and portable monitoring. This review systematically synthesizes key EBC research domains: biomarker classification encompasses small molecules, inflammation-related proteins, and pathogens. Collection methods have evolved from passive cooling (e.g., R-Tube) to active strategies (dynamic temperature control, inertial impact). Detection technologies leverage nanomaterials and microfluidics to achieve picogram-level sensitivity, shifting from single-analyte tests to multi-omics integration for comprehensive disease mechanism analysis. Wearable applications progress from proof-of-concept laboratory prototypes to scenario-specific designs, such as smart masks enabling real-time epidemic screening and continuous biomarker monitoring. A novel aspect of this review presents the EBC research framework as a 'technology cluster,' emphasizing the interdisciplinary integration of electrochemical sensing, microfluidic engineering, and the detection and clinical validation of nanomaterials. It combines biomarkers with advanced collection and detection methods to address translation bottlenecks and highlights wearable applications and multi-omics integration, positioning EBC as a revolutionary precision medical tool for early detection and non-invasive monitoring.