Asymmetric depth-filtration - a versatile and scalable approach for isolation and purification of extracellular vesicles

A novel asymmetric depth filtration (DF) approach for isolation of extracellular vesicles (EVs) from biological fluids is presented, and its performance is compared with established methods. The developed workflow is simple, inexpensive, and relatively fast. Compared with ultracentrifugation and size-exclusion chromatography, the developed method isolates EVs with higher purity and yield. Only standard laboratory equipment is needed for its implementation, which makes it suitable for low-resource locations. The described implementation of the method is suitable for EV isolation from small biological samples in diagnostic and treatment guidance applications. Following the scale-up routes adopted in the biomanufacturing of therapeutics, which routinely rely on DF as one of the product purification steps, the developed method may be scaled up to harvesting therapeutic EVs from large volumes of growth medium.