Table 1.

Examples of Methods for Extracellular Vesicle Purification^*

Method	Scalable	Advantages	Disadvantages
Magnetic bead isolation	Not currently	Fast; pure product	Costly; low yield; depends on knowledge of specific surface markers; need to remove EVs from antibodies
Ultrafiltration	Yes	Works with large volumes	Potential losses under high pressure; impure product
Differential ultracentrifugation	No	Most commonly used method; best to produce large quantities; pure product	Includes contaminants; additional isolation steps necessary; difficult to resuspend the EV pellets
Density gradient ultracentrifugation	No	Commonly used method; highest purity products	Media components interfere with EV function; volume limitations apply; slow process
High-performance liquid chromatography (size exclusion)	Yes	Ideal for large scale	Shown to preserve therapeutic activity
Size-exclusion chromatography	Yes	Good separation, removing albumin, many lipoproteins	Postcolumn concentration may be needed
Tangential flow filtration; for example, a closed system of AKTATM Flux 6 tangential flow filtration50	Yes	Ideal for industrial manufacturing; commercially available; can process the samples at a large scale	Need to purchase the device, not readily available for research
Precipitation or “salting out”	Yes	Does not require specialized equipment; fast PEG precipitation has been used to generate clinical-grade EVs	Relatively impure product; PEG may interfere with some downstream assays and processes
Asymmetric flow field-flow fractionation49	Yes	Can isolate the EVs of different sizes	Costly; may not be commercially available yet
A thermophoretic aptasensor15	Not currently	Enrich EVs conjugated with Cy5-labeled single-strand DNA aptamers; good for diagnosis	Not good for EV production; costly

^*Reiner et al.¹⁸

EV, extracellular vesicle; PEG, polyethylene glycol.