Simultaneous surface and depth neural activity recording with graphene transistor-based dual-modality probes

Area of Science:

• Neuroscience
• Materials Science
• Bioengineering

Background:

• Simultaneous neural recording from cortical surface and depth is crucial for understanding brain function.
• Existing probes often lack the flexibility and dual-modality needed for comprehensive neural activity mapping.

Purpose of the Study:

• To develop flexible, dual-modality neural probes using graphene transistors for simultaneous surface and depth neural activity recording.
• To evaluate the mechanical stability and in vivo performance of these novel probes.

Main Methods:

• Fabrication of flexible dual-modality neural probes based on graphene transistors.
• Mechanical testing under bending conditions (up to 90°).
• Finite element analysis to optimize probe tip design for tissue penetration.
• In vivo simultaneous recording of epileptiform activity in rat brains.

Main Results:

• Graphene probes demonstrated stable electrical performance even under significant bending, owing to graphene's mechanical properties.
• Finite element analysis guided the selection of a sharp tip angle (π/6) for improved tissue penetration.
• Successful in vivo simultaneous surface and depth recording of neural activity, including epileptiform events, was achieved in rats.

Conclusions:

• Graphene transistor-based dual-modality neural probes offer a stable, flexible, and versatile platform for multi-site neural recording.
• These probes facilitate the study of tempo-spatial patterns of neural activity in vivo.
• The developed technology holds promise for advancing research in neuroscience and brain disorder diagnostics.