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09:44
Design, Synthesis, and Photochemical Properties of Clickable Caged Compounds
Published on: October 15, 2019
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Encapsulation within a coordination cage modulates the reactivity of redox-active dyes
Oksana Yanshyna1, Michał J Białek2,3, Oleg V Chashchikhin1
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel.
Communications Chemistry
|January 25, 2023
Summary
A novel palladium coordination cage encapsulates resazurin and resorufin dyes, altering their optical properties and slowing their reduction. This reversible process enhances synthetic fluorescent probes for biological applications.
Area of Science:
- Supramolecular Chemistry
- Coordination Chemistry
- Chemical Biology
Background:
- Molecular confinement in nanosized spaces significantly alters physicochemical properties.
- The resazurin/resorufin redox pair is a common biological probe, but its behavior under confinement is unknown.
- Coordination cages offer controllable environments for molecular encapsulation.
Purpose of the Study:
- To investigate the effect of tight confinement on the optical and redox properties of resazurin and resorufin.
- To explore the use of a flexible palladium coordination cage for encapsulating these dyes.
- To assess the reversibility of the cage's assembly and disassembly with guest molecules.
Main Methods:
- Synthesis and characterization of a flexible PdII6L4 coordination cage.
- Encapsulation studies of resazurin and resorufin within the coordination cage.
- Spectroscopic analysis (UV-Vis, fluorescence) to determine optical property modulation.
- Kinetic studies to measure changes in redox reaction rates.
Main Results:
- The PdII6L4 cage efficiently encapsulates resazurin and resorufin as dimers.
- Encapsulation dramatically modulates the dyes' optical properties.
- Confinement significantly slows the reduction rates of both resazurin to resorufin and resorufin to dihydroresorufin.
- The cage disassembles upon dilution into PdII2L2 species, losing encapsulation ability, but reassembles upon addition of guest dyes.
Conclusions:
- A water-soluble coordination cage can reversibly modulate the optical and chemical properties of molecular redox probes.
- This system expands the utility of synthetic fluorescent probes in biological settings.
- The reversible nature of the cage assembly/disassembly offers dynamic control over probe behavior.
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