Rapid HER2-positive cell detection via high-voltage electroosmotic flow-driven microfluidic SPRi

The synergy between electroosmotic flow (EOF) and surface plasmon resonance (SPR) offers a transformative approach to overcome diffusion-limited biosensing. However,  existing voltage-driven EOF systems face critical trade-offs between high-voltage requirements and biocompatibility. Here, we present a self-powered electroosmosis-enhanced SPR immunosensor that integrates a triboelectric nanogenerator (TENG) with SPR imaging (SPRi) to achieve ultra-sensitive detection of HER2-positive cancer cells. By leveraging TENG-driven asymmetric alternating electric fields, the developed platform generates electroosmotic vortices that accelerate cellular transport velocity and enhance antigen-antibody binding efficiency, achieving a detection limit of 3 × 10⁴ cells/mL-an order of magnitude improvement over label-free SPR methods. Remarkably, the system captures HER2-positive cells within 45 s at a high throughput of cell, the detection speed increased by 20-fold. This performance, combined with label-free operation and biocompatibility, establishes a scalable framework for liquid biopsy applications.