Exosome Visualization via Electron Microscopy

For electron microscopy, exosomes were re-suspended in PBS and placed on a formvar-coated copper grid and incubated for 30 mins as described22 (link). The grid was washed with PBS and sample was fixed by placing the grid on the top of the 2% paraformaldehyde placed on the parafilm for 10 mins. Fixation was followed by several washes with deionized water and samples contrasted by adding 2% uranyl acetate for 15 mins. Samples were embedded by adding a drop of 0.13% methyl cellulose and 0.4% uranyl acetate for 10 mins. The grid was examined in a Philips CM10 transmission electron microscope and images were captured using a Gatan CCD digital camera.