Magnetic-Based Microfluidic Device for On-Chip Isolation and Detection of Tumor-Derived Exosomes

Exosomes are membrane-enclosed phospholipid extracellular vesicles, which can act as mediators of intercellular communication. Although the original features endow tumor-derived exosomes great potential as biomarkers, efficient isolation and detection methods remain challenging. Here, we presented a two-stage microfluidic platform (ExoPCD-chip), which integrates on-chip isolation and in situ electrochemical analysis of exosomes from serum. To promote exosomes capture efficiency, an improved staggered Y-shaped micropillars mixing pattern was designed to create anisotropic flow without any surface modification. By combining magnetic enrichment based on specific phosphatidylserine-Tim4 protein recognition with a new signal transduction strategy in a chip for the first time, the proposed platform enables highly sensitive detection for CD63 positive exosomes as low as 4.39 × 103 particles/mL with a linear range spanning 5 orders of magnitude, which is substantially better than the existing methods. The reduced...