Table 2.
Summary of common EV isolation methods
| Method | Description | Example | Yield | Purity/quality | Equipment/Cost | Approximate processing time | Commercial products | Reference |
|---|---|---|---|---|---|---|---|---|
| Ultracentrifugation-based methods | Size- or density-dependent isolation | 1. Differential centrifugation/Ultracentrifugation 2. Sucrose gradient ultracentrifugation | High | Protein aggregates and particulates contaminations | High equipment cost | 2.5 – 48 h | No commercial available | [75, 77–80] |
| Size-based methods | Size- or molecular weight-dependent isolation | 1. Ultrafiltration 2. Size exclusive chromatography (SEC) 3. Asymmetrical-flow field-flow fractionation (AF4) | Low (AF4) | High purity (AF4, SEC); exosomes may be deformed (ultrafiltration) | Low/moderate equipment cost (ultrafiltration and SEC ); high equipment cost (AF4) | 1 - 1.5 h (Ultrafiltration); 0.5 - 1 h (SEC); 1h (AF4) | Available, .e.g.. EVSecond column (GL Sciences) or qEV column (Izon Science) | [82–84, 98–100] |
| Immunoaffinity-based methods | Antibody-antigen interaction-dependent isolation | 1. Immunocapture 2. Immunoadsorption | Low | High purity | High reagent cost | 4 - 5 h | Available, e.g. MagaCapture™ Exosome Isolation Kit (Wako) or Exosome-Human CD9 Isolation Reagent (ThermoFisher) | [85–87] |
| Precipitation-based methods | Solubility- or dispersibility-dependent isolation | Polyethylene glycol | Dependence | Contaminated precipitates | Low equipment cost | 1 h | Available, e.g. Total Exosome Isolation Kit (Invitrogen) or ExoQuick™ Exosome Precipitation (System Biosciences) | [81, 88, 89] |
| Microfluidic-based methods | Size-, density-, or antibody-antigen interaction-dependent isolation | Microfluidic device with nanoporous membrane, immuno-chip, or porous silicon nanowires-on-micropillar structure | Dependence | High purity (porous nanowires-on-micropillar structure); EVs may be damaged (nanoporous membrane-based filtration) | Low/moderate equipment cost | 2 h (porous membrane-based filtration); 1.5 h (immuno-chip) | No commercial available | [91–95] |
| Flow cytometry-based methods | Antibody-antigen interaction-dependent isolation | 1. Fluorescent-labeled antibody-based isolation 2. Immuno-magnetic-based isolation | Low | High purity | High equipment and reagent cost | 12 h | Avaialbe, e.g. Exosome Flow Cytometry Kit (Wako) | [96, 97] |