CapSense-Flex: A Self-Powered Capillary Lab-on-Chip for Universal Electrochemical Biosensing

Capillary microfluidics offer an attractive route to pump-free point-of-care (POC) diagnostics, yet most existing platforms remain constrained by continuous flow, short residence times (-1 (R2 = 0. 9835), a 0. 1 ng mL-1 limit of detection, an imprinting factor of ≈5. 0, and n = 5). The sensor retained an ∼90% signal after 60 days at 4 °C and directly quantified cortisol in unprocessed saliva samples (1. 6-5. 0 ng mL-1) with <12% signal loss relative to PBS standards. Each capillary chip is fabricated in <7 min at <0. 40 material cost and supports plug-and-replace electrode modules for alternative MIP targets. By decoupling capillary transport from binding kinetics and eliminating external pumps or wash steps, CapSense-Flex establishes a universal architecture for scalable MIP-based biosensing across handheld, wearable, and decentralized diagnostic formats.