Intrinsically Nonswellable Multifunctional Hydrogel with Dynamic Nanoconfinement Networks for Robust Tissue-Adaptable...

Area of Science:

• Materials Science
• Biomedical Engineering
• Polymer Chemistry

Background:

• Long-term functionality of bioelectronics in vivo is critical.
• Hydrogels offer tissue adaptability but lack mechanical and electrical properties.
• Existing hydrogels suffer from water-swellability, weakening mechanical integrity.

Purpose of the Study:

• To develop a robust, intrinsically nonswellable hydrogel for bioelectronic applications.
• To enhance hydrogel properties including toughness, conductivity, and tissue adhesion.
• To demonstrate the fabrication versatility and practical utility of the developed hydrogel.

Main Methods:

• Incorporation of carboxyl- and hydroxyl-functionalized carbon nanotubes (fCNTs) for conductivity.
• Chemical modification for tissue adhesion and heat treatment for 3D printing.
• Characterization of mechanical properties (moduli, toughness, stretchability, self-healing) and electrical conductivity.

Main Results:

• Developed a nonswellable hydrogel with tissue-like moduli (10-100 kPa), high toughness (400-873 J m⁻³), and stretchability (≈1000%).
• Achieved high conductivity (≈40 S m⁻¹) maintained after deformation and rapid self-healing (≈5 min).
• Demonstrated tissue adhesion (≈50 kPa) and high-resolution 3D printability (≈100 µm).

Conclusions:

• The developed multifunctional hydrogel overcomes limitations of traditional hydrogels for bioelectronics.
• Its unique properties enable robust tissue interfacing and long-term functionality.
• Successful application in underwater electromyography and ex vivo monitoring highlights its practical potential.