Comparison of exosome isolation efficiency by ultracentrifugation and Exoquick.
precipitation. (A) Exosome fractions from ultracentrifugation or ExoquickTM precipitation were analysed by NTA. Nanoparticle concentrations per mL of original volume of media conditioned by 48 hour MCF7 culture (10.5 mL and 0.2 mL for ultracentrifugation and ExoquickTM respectively) were determined, and are expressed here relative to the ultracentrifugation results (n = 8; ± SEM). (B) CD63 immunoblot, performed under non-reducing conditions, of exosomes isolated by ultracentrifugation or ExoquickTM precipitation from 24 mL or 0.5 mL MCF7 conditioned media respectively. Exosome pellets were resuspended in equal volumes of PBS for both methods, and loading was controlled by volume. *** corresponds with P value < 0.001.