Quality and efficiency assessment of five extracellular vesicle isolation methods using resistive pulse sensing strategy

Abstract

Extracellular vesicles (EVs) have attracted great interest due to their great potential in disease diagnosis and therapy. The separation of EVs from complex biofluids with high purity is essential for the accurate analysis of EVs. Despite various methods, there is still no consensus on the best method for high-quality EVs isolation and reliable mass production. Therefore, it is important to offer a standardized method for characterizing the properties (size distribution, particle concentration and purity) of EV preparations from different isolation methods. Herein, we employed a NanoCoulter Counter based on resistive pulse sensing (RPS) strategy that enabled multi-parameter analysis of single EV to compare the quality and efficiency of different EV isolation techniques including traditional differential ultracentrifugation, ultrafiltration, size exclusion chromatography, membrane affinity binding and polymer precipitation. The data revealed that the NanoCoulter Counter based on RPS strategy was reliable and effective for the characterization of EVs. The results suggested that although higher particle concentrations were observed in three commercial isolation kits and ultrafiltration, traditional differential ultracentrifugation possessed the highest purity. In conclusion, our results from NanoCoulter Counter provided reliable evidence for the assessment of different EVs isolation method, which contributed to the development of EV-based disease biomarkers and treatments.