Early detection of cancer can significantly reduce mortality and save lives. However, the current cancer diagnosis is highly dependent on costly, complex, and invasive procedures. Thus, a great deal of effort has been devoted to exploring new technologies based on liquid biopsy. Since liquid biopsy relies on detection of circulating biomarkers from biofluids, it is critical to isolate highly purified cancer‐related biomarkers, including circulating tumor cells (CTCs), cell‐free nucleic acids (cell‐free DNA and cell‐free RNA), small extracellular vesicles (exosomes), and proteins. The current clinical purification techniques are facing a number of drawbacks including low purity, long processing time, high cost, and difficulties in standardization. Here, we review a promising solution, on‐chip electrokinetic‐based methods, that have the advantage of small sample volume requirement, minimal damage to the biomarkers, rapid, and label‐free criteria. We have also discussed the existing challenges of current on‐chip electrokinetic technologies and suggested potential solutions that may be worthy of future studies.
This work presents chemically stable and biodegradable hydrogel beads for the isolation of circulating tumor cells (CTCs) and circulating exosomes in liquid biopsy. The liquid biopsy hydrogel beads (LBbeads) consisting of alginate and poly(vinyl alcohol) hydrogels show both chemical stability and stimuli‐degradable characteristics. Unlike single‐component hydrogels, this hybrid form is not easily degraded by buffers or cell culture media while its degradable characteristic remains; thus, it is useful in bio‐applications requiring multi‐step processes with various reagents and lengthy incubation periods. We applied our platform to clinical samples for isolating two promising circulating biomarkers for a liquid biopsy, CTCs and exosomes, by conjugating the hydrogel surface with anti‐EpCAM and anti‐CD63 antibodies, respectively, thus achieving 37.4 CTCs and comparable amount of exosome recovery per 1 milliliter of blood. The results show easy device‐free isolation and retrieval of CTCs and exosomes, with recovered circulating biomarkers successfully analyzed by western blot analysis and fluorescence microscopy. We believe that this simple and versatile platform enables us to isolate prominent circulating biomarkers for clinical use in cancer diagnosis.
more » « less- NSF-PAR ID:
- 10251994
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Analysis & Sensing
- Volume:
- 1
- Issue:
- 3
- ISSN:
- 2629-2742
- Page Range / eLocation ID:
- p. 117-129
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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