Isolation and detection of exosomes on microfluidic chips
Xuan Chen, Xianglian Liu, Chuanyu Zhang, Xia He, Xianming Qin, Yuanbiao Guo, Chia‐Hung Chen, Fei Hu, Xiaofeng Guo, Dawei Zhang, Xueyong Wei
Abstract
Exosomes are a type of cell-derived extracellular vesicles (EVs) between 30 and 150 nm in diameter, which carry abundant lipid, proteins, and genetic materials. Over the past few years, exosomes have aroused great interest of researchers worldwide due to their valuable information for early diagnostics and distinct advantages for drug delivery and therapy. However, as a critical step towards clinical application, high-efficiency isolation and accurate detection methods upon exosomes are still big challenges. Benefiting from the micro/nanoscale manipulation capacity, various microfluidic techniques have been developed for isolation and detection of exosomes. This review systematically introduces microfluidic platforms engineered for size-based exosome isolation through distinct methodologies, including membrane filtration, electrical techniques, surface acoustic wave (SAW), field flow fractionation, deterministic lateral displacement (DLD), viscoelastic flow dynamics, and inertial separation. Besides, microfluidic detection methods for exosomes, including electrochemical, fluorescent, colorimetric, surface plasmon resonance (SPR), and surface-enhanced Raman scattering (SERS) have also been summarized. Further, the performances such as purity, isolation time, and detection sensitivity for each method are analyzed and compared. Finally, current challenges and outlook of the chip-level isolation and detection of exosomes in clinical applications are proposed and discussed.