Related Experiment Video
Updated: Jul 2, 2025
09:30
Using Nanoplasmon-Enhanced Scattering and Low-Magnification Microscope Imaging to Quantify Tumor-Derived Exosomes
Published on: May 24, 2019
7.4K
Single-Exosome Counting and 3D, Subdiffraction Limit Localization Using Dynamic Plasmonic Nanoaperture Label-Free
Mohammad Sadman Mallick1, Ibrahim Misbah1, Nareg Ohannesian1
1Department of Electrical and Computer Engineering, University of Houston, 4800 Calhoun Road, Houston, Texas 77204, United States of America.
Advanced Nanobiomed Research
|February 22, 2024
Summary
This study introduces dynamic Plasmonic NanO-aperture lAbel-free iMAging (D-PANORAMA) for label-free exosome characterization. The technique accurately sizes, counts, and localizes individual exosomes with 3D sub-diffraction resolution.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Analytical Chemistry
Background:
- Blood-circulating exosomes are valuable disease biomarkers due to their molecular cargo.
- Label-free characterization of exosomes is difficult due to their small size and similarity to other nanoparticles.
- Existing techniques face challenges in accurately identifying and analyzing exosomes without labels.
Purpose of the Study:
- To develop and validate a novel label-free method for characterizing exosomes.
- To demonstrate the capability of dynamic Plasmonic NanO-aperture lAbel-free iMAging (D-PANORAMA) for exosome analysis.
- To achieve 3D sub-diffraction limited localization, sizing, and counting of individual exosomes.
Main Methods:
- Utilized dynamic Plasmonic NanO-aperture lAbel-free iMAging (D-PANORAMA) on arrayed gold nanodisks on invisible substrates (AGNIS).
- Employed a bright-field technique with high surface sensitivity.
- Leveraged 2D imaging and intensity contrast for in-plane and out-of-plane localization.
Main Results:
- D-PANORAMA achieved 3D, sub-diffraction limited localization of individual 25 nm polystyrene beads.
- Demonstrated successful sizing, counting, and 3D localization of individual exosomes.
- Showcased the technique's ability to distinguish and analyze exosomes based on their binding to the AGNIS surface.
Conclusions:
- D-PANORAMA offers a robust label-free approach for exosome characterization.
- The technique provides precise 3D localization and quantification of exosomes, crucial for biomarker applications.
- This method overcomes limitations in exosome analysis, paving the way for improved clinical diagnostics.
