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Abstract The transient self‐assembly of molecules under the direction of a consumable fuel source is fundamental to biological processes such as cellular organization and motility. Such biomolecular assemblies exist in an out‐of‐equilibrium state, requiring continuous consumption of high energy molecules. At the same time, the creation of bioinspired supramolecular hydrogels has traditionally focused on associations occurring at the thermodynamic equilibrium state. Here, hydrogels are prepared from cucurbit[7]uril host–guest supramolecular interactions through transient physical crosslinking driven by the consumption of a reactive chemical fuel. Upon action from this fuel, the affinity and dynamics of CB[7]–guest recognition are altered. In this way, the lifetime of transient hydrogel formation and the dynamic modulus obtained are governed by fuel consumption, rather than being directed by equilibrium complex formation.
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This content will become publicly available on January 21, 2026
Impact of Guest Orientation in Host–Guest Supramolecular Hydrogels
Host–guest interactions have been increasingly explored for use in the dynamic physical crosslinking of polymeric precursors to form hydrogel networks. However, the orientation of guest motifs is restricted upon macromolecule conjugation. The implications of such restriction on both the kinetics and thermodynamics of the resulting host–guest supramolecular crosslinks are poorly understood. Herein, guest crosslinking motifs from controlled regioisomers are demonstrated to yield distinct material properties. Moreover, the underlying phenomena point to further unexpected impact of modular guest topology manifest on the molecular scale in both the affinity and dynamics of supramolecular complex formation.
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- Award ID(s):
- 1944875
- PAR ID:
- 10577912
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Macro Letters
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2161-1653
- Page Range / eLocation ID:
- 8 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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