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bioRxiv · 10.1101/2022.10.18.512792

MagPEG: a complete extracellular vesicle isolation/analysis solution

Abstract

Current extracellular vesicle (EV) isolation methods depend on large expensive equipment like ultracentrifuges and are laborious and time consuming. There is also currently no method available for high throughput isolation to meet clinical demands. Here, we present a method that combines our previous published ExtraPEG method and magnetic beads. Western blot and nanoparticle tracking analysis (NTA) of the purified EVs revealed higher or equivalent recovery and purity with this method compared to ExtraPEG or size exclusion chromatography (SEC) methods. With this newly developed workflow and automated liquid handling instrument, we have successfully isolated up to 96 EV samples from 5 {micro}L pre-cleared serum in 45 minutes. Moreover, DNA / small RNA / protein purification and profiling steps could be seamlessly integrated into the isolation workflow. To profile EV protein markers, EVs were lysed from the binding step and covalently bound to the surface of the beads. TotalSeq or ELISA antibody can be applied with under a standard protocol. With this extended protocol, researchers can easily complete EV isolation and protein profiling experiment within 8 hours. Taken together, we provide a high throughput method for EV isolation and molecular analyses that may be used for sensitive biomarker detection from biological fluids.

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BibTeXRIS

Sun, L., York, S. B., Pate, B., Zhang, Y., Meckes, D. G.. 2022-10-19. MagPEG: a complete extracellular vesicle isolation/analysis solution. https://doi.org/10.1101/2022.10.18.512792

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