Contents

Single Exosome Surface Enhanced Raman Spectroscopy from HEK293T Cells Using Flexible Silver Metasurfaces

Author(s): Theodore L. Brown1, Mark A. Ratner2
1Beckman Institute for Advanced Science and Technology, Urbana, IL, USA.
2Department of Chemistry, Northwestern University, Evanston, IL, USA
Theodore L. Brown
Beckman Institute for Advanced Science and Technology, Urbana, IL, USA.
Mark A. Ratner
Department of Chemistry, Northwestern University, Evanston, IL, USA

Abstract

SERS of single exosomes on flexible plasmonic substrates is the most credible when its spectroscopic interpretation is based on the physical object behind it. This study considers object gated HEK293T single exosome SERS interval ledger on flexible silver metasurface and poses the following specific question: Given the criteria of topographical and electrical eligibility, how much of the assigned Raman readout is specific evidence, and how much is mixed support? Measurement criteria include a silver metasurface with a period of 400 ± 10 nm, modulation amplitude of 70 nm–90 nm, vesicle compatible object scale of 30 nm–150 nm, excitation at 785 nm and approximately 1.5 mW power, and nine assigned Raman intervals within 600 cm−1–1700 cm−1. The analysis of the interval ledger includes the criteria of object eligibility, interval separation, evidence weight and ambiguity burden for the assigned neighbourhoods. Nine assigned windows cover 355 cm−1 out of 1100 cm−1 interval span, with 745 cm−1 remaining unassigned biochemically. The strongest protein pivots in the measurement are the windows at 810 cm−1–830 cm−1 and 940 cm−1–965 cm−1, which have higher evidence score than the corresponding mixed windows. The high wavenumber domain 1495 cm−1–1630 cm−1 is the tightest local cluster (85.2 % packing density), but is not the one with the highest evidence score. The intermediate 1200 cm−1–1370 cm−1 region has the biologically significant content of proteins and nucleic acids, contributing to the largest ambiguity burden. Conclusion: the spectrum that passed through the gate should be interpreted as a role distributed SERS profile, where two lower-wavenumber protein pivots serve as specific evidence, the upper region provides tight biochemical context and middle region serves as mixed support.

Keywords: single exosome, extracellular vesicle, surface-enhanced Raman scattering, AFM–SSRM screening, interval evidence, ambiguity burden, flexible metasurface, HEK293T
Copyright © 2026 Theodore L. Brown, Mark A. Ratner. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.