Abstract

High-Throughout Characterization of Single Exosomes and Extracellular Vesicles

George Daaboul, Chief Scientific Officer, nanoView Diagnostics, Inc.

To accurately characterize exosomes it is necessary to validate prepared samples, which is most commonly performed using nanoparticle tracking analysis (NTA) combined with proteomic analysis for exosomal proteins. As an alternative to this, Flow Cytometry (FC) has recently been used to combine the sizing and proteomic information into a single measurement. While FC is a mature tool for large cellular-sized analyses, there are a number of limitations that stem from the small-size of exosomes, specifically in terms of the number of available surface epitopes and low-signal relative to background levels, especially in complex samples. To improve the characterization of exosomes, nanoView Diagnostics has developed a label-free visible-light microarray imaging technique that allows multiplexed enumeration and sizing of individual nanovesicles captured on the sensor in a one-step assay direct-from-sample and can work with samples volumes as small as 5 µl. The exosome characterization technology collapses a number of steps into a 1-step high-throughput technique that can improve standardization of exosome preparations and facilitate translation of exosome based liquid biopsies and therapeutic developments.