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Abstract Exosomes, a subset of extracellular vesicles (EVs, 30–200‐nm diameter), serve as biomolecular snapshots of their cell of origin and vehicles for intercellular communication, playing roles in biological processes, including homeostasis maintenance and immune modulation. The large‐scale processing of exosomes for use as therapeutic vectors has been proposed, but these applications are limited by impure, low‐yield recoveries from cell culture milieu (CCM). Current isolation methods are also limited by tedious and laborious workflows, especially toward an isolation of EVs from CCM for therapeutic applications. Employed is a rapid (<10 min) EV isolation method on a capillary‐channeled polymer fiber spin‐down tip format. EVs are isolated from the CCM of suspension‐adapted human embryonic kidney cells (HEK293), one of the candidate cell lines for commercial EV production. This batch solid‐phase extraction technique allows 1012EVs to be obtained from only 100‐µl aliquots of milieu, processed using a benchtop centrifuge. The tip‐isolated EVs were characterized using transmission electron microscopy, multi‐angle light scattering, absorbance quantification, an enzyme‐linked immunosorbent assay to tetraspanin marker proteins, and a protein purity assay. It is believed that the demonstrated approach has immediate relevance in research and analytical laboratories, with opportunities for production‐level scale‐up projected.
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Isolation of Cancer-Derived Exosomes Using a Variety of Magnetic Nanostructures: From Fe3O4 Nanoparticles to Ni Nanowires
Isolating and analyzing tumor-derived exosomes (TEX) can provide important information about the state of a tumor, facilitating early diagnosis and prognosis. Since current isolation methods are mostly laborious and expensive, we propose herein a fast and cost-effective method based on a magnetic nanoplatform to isolate TEX. In this work, we have tested our method using three magnetic nanostructures: (i) Ni magnetic nanowires (MNWs) (1500 × 40 nm), (ii) Fe3O4 nanorods (NRs) (41 × 7 nm), and (iii) Fe3O4 cube-octahedral magnetosomes (MGs) (45 nm) obtained from magnetotactic bacteria. The magnetic response of these nanostructures has been characterized, and we have followed their internalization inside canine osteosarcoma OSCA-8 cells. An overall depiction has been obtained using a combination of Fluorescence and Scanning Electron Microscopies. In addition, Transmission Electron Microscopy images have shown that the nanostructures, with different signs of degradation, ended up being incorporated in endosomal compartments inside the cells. Small intra-endosomal vesicles that could be precursors for TEX have also been identified. Finally, TEX have been isolated using our magnetic isolation method and analyzed with a Nanoparticle tracking analyzer (NanoSight). We observed that the amount and purity of TEX isolated magnetically with MNWs was higher than with NRs and MGs, and they were close to the results obtained using conventional non-magnetic isolation methods.
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- Award ID(s):
- 1762884
- PAR ID:
- 10232476
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 10
- Issue:
- 9
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 1662
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/nano10091662
