Concentration measurements of extracellular vesicles (EVs) are currently incomparable between flow cytometers, due to differences in hardware configurations between various flow cytometers. Therefore, not only reference materials, but also stable biological test samples containing EVs are needed to standardise EV concentration measurements.
In work package (WP) 3, we aim to develop off-the-shelf, stable, flow cytometry compatible, ready-to-use and well-characterised biological test samples containing EVs. These biological test samples will be being prepared from human serum, plasma and urine, as these are the most widely studied body fluids with regard to EV research. Having ready-to-use biological test samples is important to avoid measurement variations due to differences in sample composition . The newly developed biological test samples will be used to validate the developed reference materials (WP1) and procedures (WP2) in an inter-laboratory comparison study.