High-Efficiency Separation of Extracellular Vesicles from Lipoproteins in Plasma by Agarose Gel Electrophoresis

Isolation and purification of extracellular vesicles (EVs) from plasma is essential to understand the EV circulation mechanism and discover biomarkers for the early detection of diseases. However, the size range of lipoprotein particles such as high density lipoprotein (HDL), low density lipoprotein (LDL), and very low density lipoprotein (VLDL) overlap that of EVs, making it difficult to remove lipoproteins from EVs. Here, we propose a method for the high efficiency separation of EVs in plasma using agarose gel electrophoresis based on their differences in size and zeta potential properties. Electrophoresis track assays revealed that EVs propagate more slowly than HDL but more quickly than LDL and VLDL in 1% agarose gel with pH 7.4 Tris-Acetate-EDTA (TAE) buffer. The size and morphology of the electrophoresis-recovered products were characterized to be consistent with typical EVs. In addition, the biological function of recovered EVs was investigated with cell uptake tests. The feasibility of this method was further verified with human plasma samples. In summary, this technique has the potential to become a convenient and efficient approach for high-purity EV separation.