Fig. 2

Evaluation of crude sEVs obtained via three different concentration methods. a Size distribution of pellets via ultrafiltration (n = 3). b Size distribution of pellets via ultracentrifugation (n = 3). c Size distribution of pellets via co-precipitation (n = 3). d The numbers of total particles and sEVs (30–150nm) in the pellets (n = 3). e The yield of the protein in pellets after concentration process (n = 3). f Coomassie brilliant blue staining of pellet. g TEM images of pellets. Contaminants of aggregated small particles (red frame) could be observed in the pellet obtained via co-precipitation method