Novel flexible Parylene neural probe with 3D sheath structure for enhancing tissue integration

Area of Science:

• Biomedical Engineering
• Neuroscience
• Materials Science

Background:

• Reliable chronic neural interfaces are crucial for understanding brain function and treating neurological disorders.
• Existing neural probes face challenges with tissue integration and signal quality over time.

Purpose of the Study:

• To design and fabricate a novel Parylene C neural probe with a 3D sheath structure for enhanced neural recording.
• To investigate the electrochemical properties of integrated platinum electrodes for neural signal acquisition.
• To develop and demonstrate an in vitro implantation procedure for the neural probe.

Main Methods:

• Fabrication of a 3D Parylene C sheath structure using thermoforming with microwire molds.
• Integration of platinum electrodes on inner and outer surfaces of the sheath for neural signal recording.
• Electrochemical characterization (cyclic voltammetry, electrochemical impedance spectroscopy) of platinum electrodes.
• In vitro implantation into an agarose brain tissue model.

Main Results:

• Successful fabrication of a 3D Parylene C neural probe with integrated platinum electrodes.
• Electrochemical characterization confirmed low electrode impedances suitable for neural recordings.
• Demonstrated feasibility of an in vitro implantation procedure.

Conclusions:

• The developed Parylene C neural probe with a 3D sheath structure shows promise for neural recording applications.
• Future work includes decorating the probe with neurotrophic factors to promote tissue ingrowth and improve chronic performance.
• This technology has the potential to enhance tissue integration and recording quality for reliable chronic neural interfaces.