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Updated: Feb 10, 2026

Monitoring Conformational Dynamics of Single Unmodified Proteins using Plasmonic Nanotweezers
Published on: March 21, 2025
Analyses of Intravesicular Exosomal Proteins Using a Nano-Plasmonic System
Jongmin Park1,2, Hyungsoon Im1,2, Seonki Hong1
1Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114.
Abstract:
Extracellular vesicles (EVs), including exosomes, are nanoscale membrane particles shed from cells and contain cellular proteins whose makeup could inform cancer diagnosis and treatment. Most analyses have focused on surface proteins while analysis of intravesicular proteins has been more challenging. Herein, we report an EV screening assay for both intravesicular and transmembrane proteins using a nanoplasmonic sensor. Termed iNPS (intravesicular nanoplasmonic system), this platform used nanohole-based surface plasmon resonance (SPR) for molecular detection. Specifically, we i) established a unified assay protocol to detect intravesicular as well as transmembrane proteins; and ii) engineered plasmonic substrates to enhance detection sensitivity. The resulting iNPS enabled sensitive (0.5 μL sample per marker) and high-throughput (a 10 × 10 array) detection for EV proteins. When applied to monitor EVs from drug-treated cancer cells, the iNPS assay revealed drug-dependent unique EV protein signatures. We envision that iNPS could be a powerful tool for comprehensive molecular screening of EVs.
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