On-Chip Pathogens Enrichment and Detection Using Dual Vortex-Enhanced Acoustofluidic Tornado

Pathogens pose significant global health risks, yet their rapid and sensitive detection remains challenging due to low concentrations in complex clinical and environmental samples. Acoustofluidic lab-on-a-chip platforms provide a promising non-contact approach for pathogen enrichment to facilitate detection; however, existing systems struggle to achieve high efficiency across the wide size spectrum of pathogens (from nanometer-scale viruses to micrometer-scale bacteria) in continuous-flow operation. Here, we present the Dual Vortex-Enhanced Acoustofluidic Tornado (D-VEAT), a microfluidic system that integrates a geometrically optimized dual-triangular gigahertz (GHz) bulk acoustic wave resonator to achieve rapid, broad-range pathogen enrichment for facilitating pathogen detection. By strategically designing the angle between the resonators and laminar flow and maximizing the edge-length-to-area ratio, the system establishes a stable, three-dimensional dual "acoustofluidic tornado". This design significantly enhances energy utilization and capture efficiency, with the coupled dual vortices achieving boundary velocities over an order of magnitude higher than traditional single-vortex structures. Furthermore, its solid-free fluidic capture strategy and adaptive vortex dynamics eliminate channel blockage and enable the system to accommodate pathogen concentrations spanning five orders of magnitude (10³-10⁸ CFU/mL). D-VEAT achieves >99% capture efficiency for 2 μm particles and >12× fluorescence enhancement for 100 nm particles, with detection limits of 1 × 10³ CFU/mL for bacteria (E. coli) and 2 × 10⁴ PFU/mL for pseudotyped coronavirus in <5 min. Compatible with ultra-low-volume samples (<5 μL) and mainstream biosensors, D-VEAT offers rapid, low-cost, and reusable diagnostics.