Extracellular vesicles (EVs) have emerged as promising targets for liquid biopsy, yet their efficient isolation and release remain technically challenging. Conventional affinity-based microfluidic chips often suffer from limited contact efficiency and releasing performance between EVs and fixed capture elements. To address this, we developed a novel microfluidic chip integrating hybrid micromixing and magnetic trapping for high-performance EV isolation, on-chip antigen profiling, and releasing. The chip features a frontend mixing zone with an S-type microchannel to induce Dean vortices, combined with herringbone structures to enhance chaotic mixing. This design ensures optimal interaction between EVs and immunomagnetic beads (IMBs) functionalized with capture antibodies. The backend trapping zone employs a low-velocity circular chamber with a central trapping well to maximize the EV-IMB retention rate (>98%) under the magnetic force. The platform enables rapid (93%) and release (>79%) or on-chip multiplexed immunolabeling of EV surface tumor biomarkers (EpCAM, PSA, CSV, CD63). Coupled with linear discriminant analysis, the chip demonstrated 100% accuracy in discrimination of cancer patients from healthy controls in early screening and >92% accuracy in distinguishing cancer subtypes, offering a robust tool for cost-effective cancer diagnosis and phenotyping.
Chen et al. (Tue,) studied this question.