Cryo‐transmission electron microscopy
TEM
To visualize LEAP‐purified pEVs, cryo‐transmission electron microscopy (TEM) was performed. The vesicles were imaged on a Talos L120C (ThermoFisher) transmission electron microscope, equipped with a LaB6 cathode filament at 120 kV (Melbourne Advanced Microscope Facility, Bio21 Institute, Australia). Cryogenic sample preparation was performed on a Vitrobot Mach IV (ThermoFisher) using lacey and holey carbon grids. For each grid, 4 μL of the sample was blotted for 7 s and plunge‐frozen in liquid ethane before imaging.