Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 16: Membranes, Vesicles and Synthetic Life-like Systems II

BP 16.9: Vortrag

Mittwoch, 11. März 2026, 12:00–12:15, BAR/0205

Interferometric and Fluorescence Nanoparticle Tracking for Analysis of Extracellular Vesicles — •Shuhan Jiang^{1, 2}, Anna Kashkanova⁴, Morgan Miller^{1, 2}, Hannarae Lee^{1, 2, 3}, Hamed Qazvini^{1, 2}, and Vahid Sandoghdar^{1, 2, 3} — ¹Max Planck Institute for the Science of Light, Erlangen, Germany — ²Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany — ³Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany — ⁴AE Eindhoven, Groene Loper 19, Flux, Netherlands

Extracellular vesicles (EVs) are considered to be important disease markers. However, their inherent heterogeneity poses a major challenge for the characterization of their physical properties and biochemical content. We combine interferometric nanoparticle tracking analysis (iNTA) with fluorescence detection to measure particle size, refractive index, and fluorescence intensity with single-molecule sensitivity. We verify that the fluorescence signal increases with particle size for dye-labeled liposomes, and that count rates shift as one changes the labeling density. In an exemplary case study applied to HEK293-derived EVs, we show that the method resolves CD9/CD81-positive subpopulations, while marker-negative particles appear more heterogeneous, suggesting contaminants or altered composition. We discuss the potential of this multimodal approach for precise differentiation of heterogeneous nanoparticles and quantitative biomarker analysis.

Keywords: nanoparticle tracking; single molecule detection; extracellular vesicles; fluorescence