Nanoparticle Tracking Analysis of Extracellular Vesicles

The EV samples were diluted to 1mL in PBS, and both particle concentration and size distribution were measured using a ZetaView PMX120 NTA instrument (Particle Metrix GmbH, Inning am Ammersee, Germany) For each measurement, 11 positions (2 cycles per position) were scanned at 25 °C. The following settings were used: auto expose; shutter speed—100; gain—28.8; offset—0; sensitivity—80 for sEVs and 75 for mEVs; frame rate—30 for sEVs and 7.5 for mEVs. The recorded videos were analyzed with a minimum area of 5, a maximum area of 1000 and a minimum brightness of 20 by ZetaView Analyze software 8.05.10 (Particle Metrix GmbH, Inning am Ammersee, Germany) [32 (link)]. When comparing the EV release from the different experimental groups, the cells were cultured under identical conditions (medium volume; tissue culture flask surface area).