Dean-Flow-Coupled Elasto-Inertial Focusing Accelerates Exosome Purification to Facilitate Single Vesicle Profiling

作者：Junjie Bai, Xuan Zhang, Xing Wei, Yu Wang, Du Cheng, Zejun Wang, Mingli Chen, Jianhua Wang · 发表于：Analytical Chemistry · 年份：2023 · DOI：10.1021/acs.analchem.2c04898 · 被引用次数：44 · 研究领域：Extracellular vesicles in disease、Microfluidic and Bio-sensing Technologies、Nanopore and Nanochannel Transport Studies

Exosomes are recognized as noteworthy biomarkers playing unprecedented roles in intercellular communication and disease diagnosis and treatment. It is a prerequisite to obtain high-purity exosomes for the comprehension of exosome biochemistry and further illustration of their functionality/mechanisms. However, the isolation of nanoscale exosomes from endogenous proteins is particularly challenging for small-volume biological samples. Herein, a Dean-flow-coupled elasto-inertial microfluidic chip (DEIC) was developed. It consists of a spiral microchannel with dimensional confined concave structures and facilitates elasto-inertial separation of exosomes with lower protein contaminants from cell culture medium and human serum. The presence of 0.15% (w/v) poly-(oxyethylene) controls the elastic lift force acting on suspended nanoscale particles and makes it feasible for field-free purification of integrity exosomes with a 70.6% recovery and a 91.4% removal rate for proteins. As a proof of concept, the technique demonstrated the individual-vesicle-level biomarker (EpCAM and PD-L1) profiling in combination with simultaneous aptamer-mediated analysis to disclose the sensibility for immune response. Overall, DEIC enables the collection of high-purity exosomes and exhibits potential in integration with downstream analyses of exosomes.