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08:32
Conducting Multiple Imaging Modes with One Fluorescence Microscope
Published on: October 28, 2018
Fluorescence detection with high time resolution: from optical microscopy to simultaneous force and fluorescence
Alexander Gaiduk1, Ralf Kühnemuth, Suren Felekyan
1Institut für Physikalische Chemie, Düsseldorf, Germany. alexander.gaiduk@uni-duesseldorf.de
Microscopy Research and Technique
|March 30, 2007
Summary
Time-correlated single photon counting (TCSPC) enables picosecond fluorescence detection over hours. This advanced technique, combined with imaging and mechanical manipulation, reveals molecular processes and conformational changes.
Area of Science:
- Biophysics
- Physical Chemistry
- Molecular Spectroscopy
Background:
- Time-correlated single photon counting (TCSPC) is a powerful technique for measuring fluorescence lifetimes with high temporal resolution.
- Investigating single molecules requires sensitive detection methods capable of resolving dynamics over a wide range of timescales.
- Understanding the relationship between mechanical properties and fluorescence is crucial for studying molecular behavior.
Purpose of the Study:
- To demonstrate the capability of advanced TCSPC for long-term, high-resolution fluorescence signal detection.
- To explore the application of TCSPC combined with optical imaging for spatial analysis of fluorescence properties.
- To investigate fluorescence signal changes in response to mechanical manipulation of single macromolecules.
Main Methods:
- Utilizing picosecond time-resolution fluorescence signal detection via time-correlated single photon counting (TCSPC).
- Employing advanced TCSPC with a clock oscillator synchronized to a pulsed laser for precise timing.
- Integrating optical imaging techniques with TCSPC for spatial fluorescence mapping.
- Combining atomic-force microscopy (AFM) for mechanical manipulation of single macromolecules.
Main Results:
- Achieved picosecond time-resolution fluorescence detection over extended periods (many hours).
- Demonstrated the ability to study molecular processes on timescales from picoseconds to seconds.
- Successfully mapped the spatial distribution of fluorescence properties in solution and on surfaces.
- Observed changes in fluorescence signals correlated with the mechanical conformations of a fluorescent dye attached to a single DNA molecule.
Conclusions:
- Advanced TCSPC is a versatile tool for investigating single-molecule dynamics and properties.
- The integration of TCSPC with optical imaging and mechanical manipulation offers a comprehensive approach to studying complex molecular systems.
- This methodology provides insights into the interplay between molecular conformation and fluorescence behavior.
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