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Rapid Fluorescence-based Characterization of Single Extracellular Vesicles in Human Blood with Nanoparticle-tracking Analysis
Published on: January 7, 2019
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Quantum Dot-Based Immunolabelling of Extracellular Vesicles and Detection Using Fluorescence-Based Nanoparticle
Eunyong Ha1, Yewon Han1, Minseop Kim1
1Department of Chemistry, College of Natural Sciences Hanyang University Seoul Republic of Korea.
Journal of Extracellular Biology
|July 23, 2025
Summary
Quantum dots conjugated to antibodies improve extracellular vesicle (EV) characterisation by enhancing detection sensitivity and enabling the profiling of EV subpopulations, offering a reliable method for EV quality control.
Area of Science:
- Biotechnology
- Nanotechnology
- Cell Biology
Background:
- Extracellular vesicles (EVs) are crucial for intercellular communication and have therapeutic potential.
- Current EV characterisation methods like scatter-based nanoparticle tracking analysis (Sc-NTA) lack selectivity.
- Existing fluorescence-based methods suffer from false positives and limited photostability.
Purpose of the Study:
- To develop a robust and sensitive method for extracellular vesicle (EV) characterisation.
- To overcome limitations of existing nanoparticle tracking analysis (NTA) techniques.
- To enable accurate profiling of EV subpopulations and improve EV quality control.
Main Methods:
- Conjugation of quantum dots (QDs) to antibodies targeting EV markers (CD9, CD63).
- Optimization of QD-based immunolabelling protocol for EVs.
- Comparison of QD-based immunolabelling with traditional Alexa dye methods using NTA.
Main Results:
- QD-based immunolabelling demonstrated enhanced detection sensitivity compared to Alexa dyes.
- The method accurately detected smaller EV populations and provided detailed size distribution.
- Subpopulations of EVs from various cell lines were successfully profiled.
Conclusions:
- Quantum dot-conjugated antibody labelling offers a sensitive and specific method for EV characterisation.
- This approach improves the accuracy of EV quantification and heterogeneity analysis.
- The developed protocol provides a reliable tool for EV quality control in research and diagnostics.
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