Hierarchical Porous Aerogel-Hydrogel Interlocking Bioelectronic Interface for Arrhythmia Management.

Area of Science:

• Materials Science
• Bioelectronics
• Biomedical Engineering

Background:

• Carbon aerogels offer exceptional electrical properties for bioelectronic applications.
• Mechanical incompatibilities and hydrogel swelling challenges hinder carbon aerogel-hydrogel hybrid performance.
• Developing robust, conductive bioelectronic interfaces is crucial for advanced medical devices.

Purpose of the Study:

• To create a stretchable, highly conductive bioelectronic interface using a carbon aerogel-hydrogel hybrid.
• To overcome the limitations of hydrogel infiltration and swelling in carbon aerogel-based materials.
• To demonstrate the efficacy of the hybrid for bioelectronic signal detection and electrical stimulation, including cardiac pacing.

Main Methods:

• Fabrication of a hierarchical porous carbon aerogel (PA) and polyvinyl alcohol (PVA) hydrogel hybrid with an interlocking network.
• Controlled infiltration of PVA into the PA structure to ensure partial PA exposure and prevent complete encapsulation.
• Characterization of the hybrid's electrical conductivity, charge storage capacity, stretchability, and long-term stability.

Main Results:

• Achieved a conductivity of 370 S·m^-1 and charge storage capacity of 1.66 mC cm^-2.
• Demonstrated remarkable stretchability (250%) and stability over three months.
• Successfully enabled ex vivo and in vivo cardiac pacing in rat models with lower pacing voltages than platinum electrodes.

Conclusions:

• The PA-PVA hybrid provides a stretchable and highly conductive bioelectronic interface.
• The interlocking network design effectively addresses challenges in hydrogel infiltration and swelling.
• The hybrid shows significant potential for arrhythmia management and advanced bioelectronic applications, including wireless in vivo monitoring and pacing.