A microcapillary chip-based particle electrophoresis system developed for characterizing extracellular vesicles (EVs) is described. So far, it is technologically difficult to analyze or identify a heterogeneous population of particles ranging from several tens to one hundred nanometers, and hence, there is a growing demand for a new analytical method of nanoparticles among researchers working on extracellular vesicles. The analytical platform presented in this chapter allows detection of individual nanoparticles or nanovesicles of less than 50 nm in diameter and enables the characterization of nanoparticles based on multiple indexes such as concentration, diameter, zeta potential, and surface antigenicity. This platform will provide a useful and easy-to-use solution for obtaining both quantitative and qualitative information on EV samples used in research and development of exosome biology and medicine.
Keywords: Brownian motion analysis; Dark-field microscopy; Exosomes; Immonoelectrophoresis; Microcapillary chip; Multiplex assay; Particle electrophoresis; Subpopulation; Zeta potential.