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Updated: May 13, 2026
15:06
Synthesis of an Intein-mediated Artificial Protein Hydrogel
Published on: January 27, 2014
Mussel-inspired histidine-based transient network metal coordination hydrogels.
Dominic E Fullenkamp1, Lihong He, Devin G Barrett
1Biomedical Engineering Department ; Chemistry of Life Processes Institute.
Macromolecules
|February 27, 2013
Summary
Researchers developed transient network hydrogels using histidine-divalent cation bonds, inspired by mussel adhesive proteins. These self-healing hydrogels show tunable properties based on metal ion coordination and dissociation rates.
Area of Science:
- Polymer Chemistry
- Materials Science
- Biomaterials Engineering
Background:
- Mussel byssal threads utilize histidine-metal coordination for self-healing and adhesion.
- Developing synthetic materials that mimic these natural properties is a key area of biomaterials research.
Purpose of the Study:
- To investigate transient network hydrogels cross-linked via histidine-divalent cation coordination.
- To understand the relationship between metal coordination, pH, and hydrogel mechanical properties.
Main Methods:
- Utilized histidine-modified star poly(ethylene glycol) (PEG) polymers.
- Employed conventional rheologic methods to study hydrogel viscoelastic properties.
- Determined equilibrium metal-binding constants using dilute solution potentiometric titration.
Main Results:
- Hydrogel properties were sensitive to metal type, pH, concentration, and ionic strength.
- Potentiometric titration yielded equilibrium constants consistent with small molecule analogs.
- Gel relaxation dynamics correlated with coordination bond dissociation rates, not equilibrium constants.
Conclusions:
- Histidine-divalent cation coordination provides a versatile cross-linking mechanism for transient hydrogels.
- Understanding pH-dependent speciation is crucial for designing effective metal-coordination hydrogels.
- Coordination bond dissociation kinetics are key to hydrogel relaxation dynamics.
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