Size-based analysis of extracellular vesicles using sequential transfer of an evaporating droplet

Lab Chip. 2019 Oct 7;19(19):3326-3336. doi: 10.1039/c9lc00526a. Epub 2019 Sep 9.

Abstract

We report spatial separation of extracellular vesicle (EVs) populations based on particle size by using an approach that exploits Marangoni flow and the coffee-ring effect in microdroplets. Sequential transfer of a drying droplet progressively increases the mean size of EVs in the sample by repeated subsampling of a droplet during coffee-ring formation. This method allows size-based sorting, separation, and eventual retrieval of EVs for RNA and protein analysis. To demonstrate the biomedical relevance of this method, EVs from prostate cancer patients were analyzed; results revealed that the expression of cancer-associated genes and proteins was higher in small EVs than in large EVs. This ability to sort EVs using a combination of coffee ring with Marangoni flow and sequential droplet-transfer allows analysis of subpopulations of EVs, and will facilitate further studies of EVs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Extracellular Vesicles / chemistry*
  • Extracellular Vesicles / genetics
  • Humans
  • MCF-7 Cells
  • Male
  • Nanoparticles / chemistry
  • Particle Size
  • Prostatic Neoplasms / chemistry*
  • Prostatic Neoplasms / diagnosis
  • Prostatic Neoplasms / genetics
  • Surface Properties
  • Tumor Cells, Cultured