Extracellular vesicles are bi-lipid membrane structures released by all types of cells in their immediate or distant environment. Their particularity lies in their nanometric size and their heterogeneity in quantity and quality.

Indeed, they are nanoparticles measuring from 30 to 1000 nm, and originating from endosomal vesicular trafficking, membrane budding, or other dynamic cellular processes. Variability also comes from the fact that these extracellular vesicles can be produced by all cells of living beings and circulate in tissues and biological fluids.

In addition, they transport various biological molecules, such as metabolites, proteins, lipids, and nucleic acids, depending on the production pathway and cellular source.

Extracellular vesicles play a significant role in intercellular communication as messengers and/or clearance products. As such, they are involved in numerous physiological and pathological processes, thus contributing to the complexity of cellular interactions and communications.

The main problems in the study of extracellular vesicles lie in their size and diversity, which involve isolation, characterization, and quantification methodologies, adapted to their very nature and the presence of other contaminating particles.