Table 3

Summary of commonly used extracellular vesicle (EV) isolation methods

Differential ultracentrifugationEVs are isolated based on their sedimentation velocity in a centrifugal forceCurrently most widely used and easy to perform
Difficulty achieving full separation of EV subcategories
Size exclusionSeparates EVs based on sizeWell characterised kits available
Requires extensive postisolation processing
Affinity separationA molecule with affinity to a surface marker on the EV is suspended in a resin or bead which ‘pulls’ EVs from complex matricesCan be highly specific for EVs
Elution of the EV from the tagged resin requires harsh buffers which can degrade the EV membrane
PrecipitationHigh molecular weight polymers are complexed with EVs and isolated by either size or density-based methodsReduces complexity of isolation protocol
Commercially available kit—ExoQuick
Requires postisolation decomplexation
Density ultracentrifugationA form of ultracentrifigation (UC) where viscosity gradients are employed to create a cushion which separates molecules into defined layersGreatly reduces copelleting substances such as cellular lipoproteins
Lower EV yields are often reported compared with differential UC
Microfluidic systemAcoustic, electric, optical, magnetic and immunoisolation of EVs from whole materialHigh purity isolation with qualitative and quantitative potential
Low volumes result in lower yield and throughput