Microfluidic Isolation of extracellular vesicles and validation through AFM and DNA amplification

TECHNOLOGY

ISSN: 0000-0000
EJEV
(2020), Vol 1, 3-10

Published online: 08 October 2020

Full Text (Bathini ~2050kb)

Srinivas Bathini 1, Shanmugasundaram Pakkiriswami 2, Duraichelvan Raju 1, Simona Badilescu 1, Anirban Ghosh 1, Rodney J Ouellette 3, Muthukumaran Packirisamy 1,*

1 Optical Bio-Microsystems Laboratory, Department of Mechanical Engineering, Concordia University, Montreal, Canada

2 Department of Biochemistry and Molecular Biology, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada

3 Atlantic Cancer Research Institute, Moncton, New Brunswick, Canada

*Correspondence to: Muthukumaran Packirisamy, Email: pmuthu@alcor.concordia.ca, Tel: +514 8482424 ext 7973


© Copyright The Author(s). This is an open access article, published under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0). This license permits non-commercial use, distribution and reproduction of this article, provided the original work is appropriately acknowledged, with correct citation details.


ABSTRACT

Extracellular vesicles (EVs) or exosomes are nano-sized particles containing lipids, proteins, mRNAs, and microRNAs from their origin cells, thus playing a critical role in cell-to-cell communication. The currently existing detection methods are expensive, time-consuming and lack in yield and purity. Here, we present a simple microfluidics-based method to capture EVs by a novel affinity-based approach, using, instead of antibodies, a synthetic polypeptide, Vn96, that binds to the heat shock proteins (HSPs) present on the surface of EVs/exosomes. The captured EVs are detected by using the high sensitivity of the Localized Surface Plasmon Resonance (LSPR) property of gold nano-islands to any changes in their local environment. The microfluidic devices developed for the isolation of exosomes, contain multiple channels and a collection chamber to capture EVs. The capture and detection ability of the device is validated by AFM measurements of isolated EVs from the device and the measurement of gene copy number using droplet digital PCR (ddPCR). The results indicate that the developed device can capture and isolate the EVs from a very low sample volume, in less than 30 minutes, without affecting their size and shape, a major advantage compared to existing methods. Thus, the device can be considered as a prospective point of care apparatus for diagnostics in a clinical setting.

Keywords: Lab-on a chip, early diagnosis of cancer, microfluidics, ddPCR