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bioRxiv · 10.1101/2021.12.28.474334

Fast and specific enrichment of cancer-related exosomes by DNA-nanoweight-assisted centrifugation

lu, z.·yuxyan, m.·shi, y.·jia, b.·li, x.·Li, Z.
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Abstract

Exosomes are nanoscale membrane vesicles actively released by cells and play an important role in the diagnosis of cancer-related diseases. However, it is challenging to efficiently enrich exosomes from extracellular fluids. In this work, we used DNA-tetrahedron as a nanoweight during centrifugation to precisely enrich tumor exosomes from a complex biological environment. Two different DNA tetrahedral nanostructures (DTAs), each carrying a specific aptamer for exosome biomarker recognition, were incubated with clinical samples simultaneously. One DTA triggered the cross-linking of multiple target exosomes, and therefore enabled low-speed and fast centrifugation for enrichment. The other DTA further narrowed down the target exosome subtype and initiated a hybridization chain reaction (HCR) for sensitive signal amplification. The method enabled the detection of 180 MCF-7-derived exosomes per microliter and 560 HepG2-derived exosomes per microliter, with 1000-fold higher sensitivity than conventional ELISA. This easy-to-operate method can enrich exosomes with excellent specificity and therefore will be appealing in biomedical research and clinical diagnosis.

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lu, z., yuxyan, m., shi, y., jia, b., li, x., Li, Z.. 2021-12-28. Fast and specific enrichment of cancer-related exosomes by DNA-nanoweight-assisted centrifugation. https://doi.org/10.1101/2021.12.28.474334

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