Muscle-Inspired Self-Healing Hydrogels for Strain and Temperature Sensor

Area of Science:

• Materials Science
• Bioelectronics
• Polymer Chemistry

Background:

• Self-healing hydrogels are promising for bioelectronic devices due to their biocompatibility and mechanical compliance.
• Current limitations include poor stretchability, sensitivity, subzero brittleness, and single sensory function.

Purpose of the Study:

• To develop a self-healing, dual-sensory hydrogel sensor with enhanced mechanical and thermal properties.
• To overcome the limitations of existing hydrogel-based sensors for broader bioelectronic applications.

Main Methods:

• Fabrication of a hydrogel sensor inspired by muscle microstructures and mechano-transduction.
• Incorporation of a glycerol/water binary solvent system to enhance self-healing and thermal tolerance.
• Characterization of mechanical properties, stretchability, sensitivity, and thermosensation.

Main Results:

• Achieved 90.8% self-healing efficiency and long-lasting thermal tolerance.
• Demonstrated high gauge factor (18.28) over a broad strain range (268.9%) with a low limit of detection (5% strain).
• Exhibited satisfactory thermosensation (-0.016 °C⁻¹) and temperature resolution (2.7 °C), with effective subzero self-healing.

Conclusions:

• The developed hydrogel sensor overcomes key limitations of existing bioelectronic devices.
• Its mechanoreception and thermosensitive capabilities enable applications like flexible keyboards and fever indicators.
• The glycerol/water system is crucial for achieving subzero self-healing, water retention, and adhesion.