Fig. 3From: Bolstering the secretion and bioactivities of umbilical cord MSC-derived extracellular vesicles with 3D culture and priming in chemically defined media Internal and external characteristics of EVs. a The FTIR spectra of EVs in the range of 900–4000 cm−1 wavelength to distinguish the surface compositions of EVs. b The 3D PCA score plot to classify EVs from FTIR analysis. c The representative images of cytokine array membranes of 2D CDM EV, 3D CDM EV, and TI3D CDM EV. d The comparison of expression levels for representative cytokines. e The scatter plot of three different EVs by the results of cytokine arraysBack to article page