3D Printed Skull Cap and Benchtop Fabricated Microwire-Based Microelectrode Array for Custom Rat Brain Recordings

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Microwire microelectrode arrays (MEAs) are valuable for chronic electrophysiological recordings but face challenges in fabrication and implantation.
• Current methods are time-consuming and require significant manual skill, limiting accessibility and scalability.

Purpose of the Study:

• To develop a streamlined and cost-effective approach for fabricating and implanting microwire MEAs.
• To improve the accuracy and reduce the manual dependency of multi-MEA implantation in rodents.

Main Methods:

• A computer-aided designed (CAD) and 3D-printed skull cap was created for precise MEA implantation.
• A novel benchtop fabrication method was developed for low-cost, custom microwire MEAs.
• A 32-channel, 4-MEA recording system was prototyped and tested in Sprague Dawley rats.

Main Results:

• The 3D-printed skull cap demonstrated high accuracy and conformity across various rat subjects.
• The custom-fabricated MEAs successfully recorded neural spiking activity for over five months.
• The system achieved minimal bregma alignment error (A/P: 0.25 mm, M/L: 0.07 mm).

Conclusions:

• The integrated approach of a 3D-printed skull cap and benchtop fabrication significantly reduces the cost and complexity of microwire MEA implementation.
• This method empowers neuroscience research groups to perform in-house design, fabrication, and implantation of customizable MEAs.
• The developed platform offers a shorter lead time for design modifications and iterations, accelerating research progress.