A novel microfluidic chip based on an impedance-enhanced electrochemical immunoassay.

The article focuses on the development of a novel microfluidic device employing an impedance-enhanced electrochemical immunoassay (IE-ECIA) for rapid, portable, and cost-effective detection of COVID-19. This device integrates antibody-coated magnetic and dielectric micro/nanobeads within a microfluidic chip, using electrochemical impedance spectroscopy (EIS) combined with a microcontroller, micropump, and impedance converter to quantitatively analyze viral proteins without the need for fixed beads or modified electrodes. An analytical modeling algorithm based on equivalent circuit parameters enhances detection sensitivity by distinguishing impedance changes related to antigen presence, achieving high accuracy and throughput while minimizing reagent use. The platform demonstrates potential for point-of-care diagnostics and personalized medicine by enabling automated, high-throughput screening in a compact and economical format.