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Simultaneous Multicolor Imaging of Biological Structures with Fluorescence Photoactivation Localization Microscopy
Published on: December 9, 2013
Synchronously amplified fluorescence image recovery (SAFIRe)
Chris I Richards1, Jung-Cheng Hsiang, Robert M Dickson
1School of Chemistry and Biochemistry and Petit Institute for Biosciences and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
The Journal of Physical Chemistry. B
|November 12, 2009
Summary
Optical depopulation of organic fluorophore triplet states enhances fluorescence brightness and reduces background. This method, synchronously amplified fluorescence image recovery (SAFIRe) microscopy, significantly boosts sensitivity for imaging applications.
Area of Science:
- Photochemistry
- Fluorescence Microscopy
- Spectroscopy
Background:
- Fluorescence intermittency limits brightness in single molecule and bulk fluorescence imaging.
- Triplet state formation in organic fluorophores contributes to fluorescence quenching and reduced signal intensity.
- Existing fluorescence techniques face challenges in achieving high sensitivity and low background noise.
Purpose of the Study:
- To demonstrate optical depopulation of organic fluorophore triplet states for enhanced fluorescence.
- To introduce synchronously amplified fluorescence image recovery (SAFIRe) microscopy for increased sensitivity.
- To identify photophysical characteristics for improved fluorophore design in SAFIRe microscopy.
Main Methods:
- Modulating a secondary laser excitation to depopulate long-lived triplet states.
- Synchronously detecting fluorescence modulation for selective signal extraction.
- Utilizing xanthene dyes with efficient triplet-state formation for method validation.
Main Results:
- Achieved up to 5-fold increases in solution-based fluorescence compared to primary laser excitation alone.
- Demonstrated dynamic control of signal modulation by varying secondary laser frequency.
- Successfully reduced background noise through synchronous fluorescence modulation.
Conclusions:
- Optical depopulation of triplet states offers a viable strategy to increase fluorescence brightness and sensitivity.
- SAFIRe microscopy enables selective fluorescence enhancement and background reduction.
- Tailoring dye photophysics is crucial for optimizing fluorophores in SAFIRe microscopy.
