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Updated: Aug 6, 2026
09:26
DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
Cucurbit[6]uril-monoazide: towards functional CB[6]-tethered DNA (pseudo)rotaxanes
Noah Beltrami1, Soumen Pradhan2,1, Nathan A Rudman3
1Department of Chemistry, Tulane University 2015 Percival Stern Hall New Orleans Louisiana 70118 USA.
Chemical Science
|July 23, 2026
Summary
Researchers synthesized a novel cucurbit[6]uril (CB[6]) derivative, CB[6]-monoazide, enabling direct conjugation to DNA. This breakthrough facilitates advanced applications in host-guest chemistry and bioimaging.
Area of Science:
- Supramolecular Chemistry
- Chemical Biology
- Materials Science
Background:
- Cucurbit[6]uril (CB[6]) is a key host molecule with applications in molecular recognition and click chemistry.
- Functionalizing CB[6] for biomacromolecule conjugation is essential for biomedical and bioimaging applications.
- Previous research lacked CB[6] derivatives suitable for direct one-to-one conjugation.
Purpose of the Study:
- To synthesize a novel CB[6] derivative for direct covalent attachment to biomacromolecules.
- To develop new CB[6]-DNA conjugates for advanced applications.
- To explore host-DNA rotaxane and pseudorotaxane structures.
Main Methods:
- Synthesis of CB[6]-monoazide (CB[6]-N3).
- Strain-promoted azide-alkyne cycloaddition for DNA conjugation.
- Utilizing orthogonal recognition properties of DNA and CB[6] domains.
- Developing host-DNA rotaxanes and pseudorotaxane DNA duplexes.
Main Results:
- Successfully synthesized the first CB[6]-monoazide derivative.
- Demonstrated efficient conjugation of CB[6]-N3 to DNA via click chemistry.
- Constructed a host-DNA rotaxane using CB[6]-facilitated click chemistry.
- Developed a pseudorotaxane DNA duplex for sequence detection using CB[6]-mediated xenon hyper-CEST signaling.
Conclusions:
- The synthesized CB[6]-monoazide derivative is a versatile tool for creating functional CB[6]-biomacromolecule conjugates.
- These conjugates enable novel supramolecular architectures like rotaxanes and pseudorotaxanes.
- The developed systems hold promise for advanced biomedical and bioimaging applications, including molecular sensing.
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