Accurate characterization of extracellular vesicles (EVs), including exosomes and microvesicles, is essential to obtain further knowledge on the biological relevance of EVs. Tunable resistive pulse sensing (tRPS) has shown promise as a method for single particle-based quantification and size profiling of EVs. Here, we describe the technical background of tRPS and its applications for EV characterization. Besides the standard protocol, we describe an alternative protocol, in which samples are spiked with polystyrene beads of known size and concentration. This alternative protocol can be used to overcome some of the challenges of direct EV characterization in biological fluids.
Keywords: Characterization; Exosomes; Extracellular vesicles; Microvesicles; Quantification; Resistive pulse sensing; Size distribution; qNano.