Extracellular vesicles (EVs) – nanoscale membranous particles that carry multiple proteins and nucleic acid cargoes from their mother cells of origin into circulation – have enormous potential as biomarkers. However, devices appropriately scaled to the nanoscale to match the size of EVs (30–200 nm) have orders of magnitude too low throughput to process clinical samples (1012EVs mL−1in serum). To address this challenge, we develop a novel approach that incorporates billions of nanomagnetic sorters that act in parallel to precisely isolate sparse EVs based on immunomagnetic labeling directly from clinical samples at flow rates billions of times greater than that of a single nanofluidic device. To fabricate these chips, the ferromagnetic metals are electro‐deposited into a self‐assembled microlattice, achieving >109nanoscale magnetophoretic sorting devices in a 3D postage stamp‐sized lattice with >70x magnetic traps and >20x enrichment of magnetic nanoparticles versus our previous work. The immunomagnetically labeled EVs are isolated and achieve a ≈100% increase in yield as well as increased purity compared to conventional methods. Building on the proof‐of‐concept demonstrations in this manuscript, this new approach has the potential to enhance the future clinical translation of EV biomarkers by enabling rapid, sensitive, and specific isolation of EV subpopulations from clinical samples.
This content will become publicly available on December 1, 2024
- Award ID(s):
- 2046037
- NSF-PAR ID:
- 10479678
- Publisher / Repository:
- natureportfolio
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Basic Protocol 1 : Pre‐analytic fluid collection and processingBasic Protocol 2 : Exosome isolation by ultracentrifugationAlternate Protocol 1 : Exosome isolation by precipitationBasic Protocol 3 : Analysis of exosomes by NanoSight nanoparticle tracking analysisAlternate Protocol 2 : Analysis of exosomes by flow cytometry and imaging flow cytometryBasic Protocol 4 : Downstream analysis of exosomes using high‐performance liquid chromatographyBasic Protocol 5 : Downstream analysis of the exosome proteome using nano‐flow liquid chromatography–mass spectrometry -
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