Polymer Casting and Water Immersion-Based Large-Area Graphene Transfer for Flexible Electronics Fabrication

Area of Science:

• Materials Science
• Biomedical Engineering
• Nanotechnology

Background:

• Developing implantable flexible electronic devices requires efficient methods for transferring materials like graphene onto biodegradable substrates.
• Existing graphene transfer methods face challenges in scalability, efficiency, and maintaining material integrity for biomedical applications.

Purpose of the Study:

• To develop a high-throughput, efficient, and scalable method for transferring large-area graphene onto biodegradable polymer substrates.
• To fabricate functional, conductive, and cytocompatible implantable flexible electronic devices for tissue regeneration.

Main Methods:

• A novel method combining low-temperature graphene treatment, laser engraving, polymer casting, and water immersion for large-area graphene transfer.
• Fabrication of graphene-based flexible electronic devices, including electrode cuffs and piezoelectric devices.
• In vitro and in vivo mimicking condition testing for graphene stability and conductivity, along with in vitro cytocompatibility assessments.

Main Results:

• Achieved high-efficiency (∼100%) large-area graphene transfer with reduced roughness and enhanced hydrophobicity.
• Transferred graphene exhibited excellent stability, structural integrity, and high conductivity (∼40 Ω/sq) under various conditions.
• Demonstrated in vitro cytocompatibility and successful fabrication of functional flexible electronic devices that generated output voltages for cell/tissue regeneration.

Conclusions:

• The developed large-area graphene transfer method is efficient, scalable, and suitable for fabricating implantable flexible electronic devices.
• The fabricated devices show promise for stimulating cell and tissue regeneration.
• The method's ease of handling and implantation feasibility were confirmed through ex vivo surgeries.