Pillar of Engineering Product Development , Singapore University of Technology and Design , Singapore 487372 , Singapore.
Anal Chem. 2019 Apr 2;91(7):4577-4584. doi: 10.1021/acs.analchem.8b05749. Epub 2019 Mar 13.
Exosomes, submicron membrane vesicles (30-200 nm) secreted by almost all cells, containing significant information such as proteins, microRNAs and DNAs, are closely associated with disease diagnostic and prognostic tests for liquid biopsy in clinical practice. However, their inherently small sizes lead to great challenges for isolating them from complex body fluids with high-throughput and high-purity. In this work, a reverse wavy channel structure using viscoelastic fluids with the addition of biocompatible polymer was presented for elasto-inertial focusing and sorting of submicron particles and exosomes. The microfluidic periodically reversed Dean secondary flow generated by repeated wavy channel structures could facilitate particle focusing compared with traditional straight channels. Four differently sized fluorescent submicron spheres (1 μm, 500 nm, 300 and 100 nm) were used to study the focusing behavior under various conditions. We have achieved simple, high-throughput, and label-free sorting of exosomes with purity higher than 92% and recovery higher than 81%. This developed elasto-inertial exosome sorting technique may provide a promising platform in various exosome-related biological research and pharmaceutical applications.
外泌体是几乎所有细胞分泌的亚微米膜囊泡（30-200nm），其中包含蛋白质、microRNAs 和 DNA 等重要信息，与临床实践中的液体活检疾病诊断和预后检测密切相关。然而，由于其本身尺寸较小，因此从复杂的体液中以高通量和高纯度分离它们具有很大的挑战性。在这项工作中，提出了一种使用粘弹性流体和添加生物相容性聚合物的反向波浪形通道结构，用于亚微米颗粒和外泌体的弹流惯性聚焦和分选。通过重复的波浪形通道结构产生的微流周期性反向 Dean 二次流可以促进颗粒聚焦，与传统的直通道相比。使用四个不同尺寸的荧光亚微米球（1μm、500nm、300nm 和 100nm）来研究不同条件下的聚焦行为。我们已经实现了简单、高通量、无标记的外泌体分选，纯度高于 92%，回收率高于 81%。这种开发的弹流惯性外泌体分选技术可能为各种外泌体相关的生物学研究和药物应用提供了一个有前途的平台。
