Conductive and Adhesive Granular Alginate Hydrogels for On-Tissue Writable Bioelectronics

Area of Science:

• Materials Science
• Bioelectronics
• Polymer Chemistry

Background:

• Conductive hydrogels are crucial for bioelectronics, offering tissue-like properties and restoring electrophysiological function.
• Current conductive hydrogels lack sufficient tissue adhesion, necessitating additional medical glues for fixation.
• Existing fabrication methods for conductive hydrogels are often complex and limit their application.

Purpose of the Study:

• To develop an intrinsically conductive and tissue-adhesive granular hydrogel.
• To overcome the limitations of weak tissue adhesion in current conductive hydrogels.
• To create an injectable and printable hydrogel for seamless integration in bioelectronic devices.

Main Methods:

• Fabrication of a granular hydrogel using electrohydrodynamic spraying.
• Incorporation of a conductive polymer (PEDOT:PSS) and an adhesive polymer (catechol-conjugated alginate).
• Utilized calcium ion crosslinking for easy fabrication of the alginate-catechol-PEDOT:PSS composite (ACP).

Main Results:

• The fabricated ACP hydrogel demonstrated intrinsic conductivity comparable to muscle tissue.
• ACP exhibited excellent tissue-adhesive properties and shear-thinning behavior.
• The granular structure allowed for injectability and on-tissue printing via syringe.

Conclusions:

• The developed multifunctional granular hydrogel addresses the need for improved adhesion and injectability in conductive biomaterials.
• This novel hydrogel shows significant potential for applications in soft and flexible electronics, bridging human-machine interfaces.
• The ACP hydrogel offers a promising platform for advanced tissue engineering and regenerative medicine.