A 3D-Printing-Based Optogenetic Neural Stimulator Integrated With Three Neural Recording Channels

Area of Science:

• Biomedical Engineering
• Neuroscience
• Materials Science

Background:

• Optogenetic devices traditionally require complex microfabrication.
• A need exists for simplified, accessible methods for creating neural interfaces.

Purpose of the Study:

• To present a novel optical neural modulation device integrated with neural recording capabilities.
• To demonstrate the feasibility of using 3D printing for fabricating such integrated neural devices.

Main Methods:

• The device was primarily fabricated using 3D printing with two-photon polymerization (2PP) technology.
• It comprises two 3D-printed layers: one for a light-emitting diode (LED) and another for platinum wire recording channels.
• Assembly involved 3D-printed alignment features, and device characterization included electrochemical impedance spectroscopy (EIS).

Main Results:

• Successful fabrication of a 3D-printed device integrating an LED for optical stimulation and multiple recording channels.
• Electrochemical impedance spectroscopy confirmed the functionality of the integrated recording channels.
• The device was successfully implanted in a mouse brain, demonstrating simultaneous optical stimulation and neural signal recording.

Conclusions:

• 3D printing offers a viable and simplified alternative to microfabrication for creating integrated optogenetic and neural recording devices.
• The developed device enables simultaneous optical neural modulation and recording, validated in vivo.
• This approach has the potential to advance neural interface technologies through accessible fabrication methods.