Measurement of cancer biomarker enrichment in exosomes: separation using both AF4 and CF3

Asymmetrical flow field-flow fractionation (AF4) and centrifugal field-flow fractionation (CF3) are high resolution separation techniques for fractionation of macromolecules and biological nanoparticles based on their hydrodynamic size (AF4) and mass (CF3).

In this study the goal was to characterize the MCF-7 tumor exosome sample by size using AF4 coupled to multi angle light scattering (MALS), and by mass using CF3. The density of exosomes in CF3 fractions was obtained using hydrodynamic diameter and buoyant mass measured by nano tracking analysis (NTA) and CF3 respectively. Fractions were collected along both size and mass distributions and analyzed by polymerase chain reaction (PCR) for enrichment of the micro-RNA21 (miR21) cancer biomarker.