Abstract:
This study introduces a rapid, cost-effective method for fabricating three-dimensional microelectrode arrays (3D MEAs) using makerspace microfabrication and 3D printing. These MEAs were developed to interface with peripheral nerve-on-a-chip platforms, enabling high-throughput electrophysiological analysis. The device demonstrated reliable electrical, chemical, and biological performance, providing a scalable tool for drug screening and toxicity testing in vitro.
Key Learnings
- 3D microelectrode arrays can be rapidly fabricated without cleanroom reliance using 3D printing and stencil metallization.
- Platinum-coated microelectrodes significantly reduced impedance, improving signal fidelity for neural recordings.
- Integration with nerve-on-a-chip platforms enables functional recording and stimulation of dorsal root ganglion (DRG) cells.
- Device components showed variable biocompatibility; surface modifications improved viability up to 70%.
- The approach allows for scalable, customizable electrophysiological platforms suited for in vitro drug screening.
Methods
- 3D microelectrode arrays were printed using stereolithography (SLA) and metallized with Ti/Au using stencil masks.
- Electroless platinum plating enhanced electrode conductivity and reduced impedance.
- SiO₂ insulation was applied and patterned with laser micromachining to define 30 µm x 30 µm microelectrodes.
- DRG neurons were cultured on the devices to assess biocompatibility, functionality, and electrophysiological performance.
- Impedance and cyclic voltammetry were used to characterize electrical properties.
Conclusions
The 3D printed MEAs demonstrated comparable performance to complex, cleanroom-fabricated devices, with the added benefits of scalability, cost-effectiveness, and rapid prototyping. Their successful integration with nerve-on-a-chip systems validates their potential for broader adoption in preclinical drug testing, enabling functional readouts from physiologically relevant 3D neural models.
