Exosomes are small vesicles secreted by most cell types, formed by inward budding of endocytic compartments, and released into the extracellular medium. They may serve functions such as eliminating unnecessary proteins or facilitating intercellular communication. Exosomes are purified from cell culture supernatants or biological fluids using methods like differential ultracentrifugation, filtration, or immunomagnetic isolation. The purification process involves multiple centrifugation steps to remove large debris and isolate exosomes, followed by washing and resuspension. Exosomes can be characterized using electron microscopy, SDS-PAGE, and immunoblotting. The purification protocols described include steps for isolating exosomes from viscous fluids and using immunomagnetic beads for exosome capture. Exosome characterization involves morphological analysis, protein content assessment, and physical property analysis. The protocols also include methods for preparing exosome production medium and analyzing exosomes using electron microscopy and immunogold labeling. The goal is to provide reliable methods for exosome purification and characterization to ensure their identity and purity for further functional studies.Exosomes are small vesicles secreted by most cell types, formed by inward budding of endocytic compartments, and released into the extracellular medium. They may serve functions such as eliminating unnecessary proteins or facilitating intercellular communication. Exosomes are purified from cell culture supernatants or biological fluids using methods like differential ultracentrifugation, filtration, or immunomagnetic isolation. The purification process involves multiple centrifugation steps to remove large debris and isolate exosomes, followed by washing and resuspension. Exosomes can be characterized using electron microscopy, SDS-PAGE, and immunoblotting. The purification protocols described include steps for isolating exosomes from viscous fluids and using immunomagnetic beads for exosome capture. Exosome characterization involves morphological analysis, protein content assessment, and physical property analysis. The protocols also include methods for preparing exosome production medium and analyzing exosomes using electron microscopy and immunogold labeling. The goal is to provide reliable methods for exosome purification and characterization to ensure their identity and purity for further functional studies.