Fast and stable photochromic oxazines for fluorescence switching
Erhan Deniz1, Massimiliano Tomasulo, Janet Cusido
1Laboratory for Molecular Photonics, Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, Florida 33146-0431, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|May 20, 2011
Summary
Researchers developed novel photochromic switches for fluorescence microscopy. These new oxazine-based switches offer rapid, reversible control over fluorescence, improving super-resolution imaging capabilities for nanoscale biological visualization.
Area of Science:
- Photochemistry
- Molecular Engineering
- Super-resolution Microscopy
Background:
- Diffraction limits spatial resolution in fluorescence microscopy.
- Photochromic compounds offer optical control over fluorescence.
- Existing fluorophore-photochrome dyads exhibit slow switching and poor fatigue resistance.
Purpose of the Study:
- To engineer photochromic switches with improved switching speed and fatigue resistance.
- To develop molecular constructs for reversible fluorescence modulation.
- To enhance capabilities for super-resolution imaging and nanoscale biological visualization.
Main Methods:
- Synthesized a new family of photochromic switches based on oxazine ring photoinduced opening and thermal closing.
- Engineered fluorophore-photochrome dyads by attaching chromophoric fragments to the oxazine ring.
- Investigated photochemical and photophysical properties, including switching speed and fatigue resistance.
Main Results:
- Developed oxazine-based photochromic switches with nanosecond-microsecond switching times.
- Achieved thousands of switching cycles without degradation, demonstrating excellent fatigue resistance.
- Successfully modulated fluorescence in microseconds using borondipyrromethene or coumarin fluorophore-oxazine photochrome dyads.
Conclusions:
- The novel oxazine-based photochromic switches significantly improve upon existing technologies.
- These molecular constructs enable rapid, reversible fluorescence control for advanced imaging.
- The developed dyads hold promise for super-resolution microscopy and nanoscale biological imaging.
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