Cracking-Directed Dynamic Liquid Bridging for Autonomous Microdroplet Recession and Enrichment

• • Achieved 14.2-fold enhancement in enrichment efficiency for airborne pathogenic agents compared to conventional flat surfaces, demonstrating superior capture capability for microdroplets (<20 μm). • • Utilized stretchable elastomeric substrate with island-like microstructures; controlled fracture under longitudinal tensile stress yields directionally oriented cracks that generate localized capillary forces to overcome CAH. • • The crack-mediated capillary bridging strategy enables autonomous microdroplet recession and enrichment without external stimulation, addressing limitations of gradient-based methods at micro-scale. • • Integration of fracture mechanics with capillary-driven fluid dynamics provides a foundational framework for next-generation microfluidic systems, with potential in biosensing and pollutant analysis.