Probing Trapped Extracellular Vesicles by Surface-Enhanced Raman Spectroscopy

Extracellular vesicles (EVs) are released by nearly all cell types within the human body and have been found to play important biological roles including cell-to-cell communication, apoptosis and tissue repair. Lacking cellular machinery, these nano-sized vesicles carry functional proteins and nucleic acids from their parent cells, providing insight into biomarkers present in healthy, cancerous and diseased cells. EVs may be isolated from biofluids such as from blood or urine. Their detection and characterization holds extreme potential in developing less invasive disease detection and treatment methods. In this work, we propose use of lithographic techniques to fabricate platforms to allow for molecular-level characterization by surface-enhanced Raman spectra (SERS). Two methods of lithography are proposed to probe spectral signatures of individual EVs without use of labelling agents. SERS spectra are acquired for EVs released from two cell lines, allowing for determination of the diversity existent within a cell line, and amongst different cell lines