Fig. 6

(a) Mean fluorescence (log scaled) of mEVs under confocal microscopy loaded with Calcein-AM post-lyophilization after removal of exogenous dye via Sepharose G50 spin column. N = 6 images, error bars are representative of standard deviation within each group; biological duplicates. No signal was observed in HEPES control, 10mM TH, and 50mM sucrose groups (Images in Figure S6). Multiple T tests with Bonferroni Correction (α = 0.05), reveals significant differences between fresh and 25mM TH | 75mM TH and between 25 mM TH and 50mM TH | 50mM TH + W. N = 6 images, 3 ROIs each (b) CTDR: DAPI fluorescent ratios (log-scaled) of CTDR loaded fresh mEVs supplemented with TH (50mM) and TH (50mM) + Tryptophan (W; 100 µM) on MDCK cells and 50mM TH + 100 μm Tryptophan mEVs loaded with CTDR uptake post-lyophilization over time in room temperature storage, biological triplicates with N = 10 pictures per sample, outliers removed. (d) Western blotting of lyophilized mEV isolate for CD9, TSG-101, and negative expression of Calnexin. Lyophilized samples were stored at RT for 1 month