Bioinspired Oxidation-Resistant Catechol-like Sliding Ring Polyrotaxane Hydrogels

Area of Science:

• Materials Science
• Biomedical Engineering
• Polymer Chemistry

Background:

• Adaptable hydrogels are crucial for addressing tissue defects in biomedical applications.
• Traditional catechol-based hydrogels face limitations due to oxidation and irreversible crosslinking.

Purpose of the Study:

• To develop novel, oxidation-resistant hydrogels using functionalized polyrotaxane (PR) polymers.
• To explore the potential of hydroxypyridinone (HOPO) moieties for creating stable, adaptable hydrogels.

Main Methods:

• Polyrotaxane polymers were functionalized with hydroxypyridinone (HOPO) moieties.
• Hydrogels were formed via supramolecular assembly upon contact with Fe(III) solution at physiological pH.
• Mechanical properties and cytocompatibility were evaluated.

Main Results:

• The HOPO-functionalized PR polymers formed hydrogels with excellent oxidative resistance, preventing quinone formation.
• Hydrogel formation relied on metallic coordination crosslinking, enhanced by PR sliding-ring synergy and reversible HOPO interactions.
• The resulting hydrogels exhibited improved mechanical behavior and were cytocompatible.

Conclusions:

• Innovative, cytocompatible, and oxidation-resistant hydrogels were successfully developed using HOPO-functionalized PR.
• These hydrogels offer reversible crosslinking and improved mechanical properties, suitable for biomedical applications.
• The adaptable nature of these hydrogels makes them promising for use as structural self-materials.