Two-Photon Polymerization 3D-Printing of Micro-scale Neuronal Cell Culture Devices

Area of Science:

• Neuroscience
• Biotechnology
• Materials Science

Background:

• Traditional neuronal cultures lack 3D structure and realistic synaptic connectivity, limiting studies on brain function and pathophysiology.
• Achieving ex vivo structured synaptic connectivity is crucial for understanding neural rhythms, plasticity, and disease.

Purpose of the Study:

• To develop a rapid and affordable method for fabricating microfluidic devices for culturing modular neuronal networks.
• To enable controlled, directed axonal outgrowth and study unidirectional synaptic interactions in vitro.
• To integrate microelectrode arrays for monitoring bioelectrical activity in interconnected neuronal modules.

Main Methods:

• Utilizing two-photon polymerization (2PP) 3D printing to fabricate polydimethyl-siloxane (PDMS) microfluidic devices with micrometer precision.
• Designing a two-chamber device to physically constrain and direct neuronal connectivity.
• Employing commercial microelectrode arrays for in vitro multisite extracellular recordings of rat cortical neuronal cultures.

Main Results:

• Demonstrated rapid and cost-effective prototyping of PDMS microfluidic devices using 2PP.
• Successfully cultured modular neuronal networks with constrained, asymmetric axonal outgrowth between chambers.
• Monitored functional consequences of unidirectional synaptic interactions via simultaneous bioelectrical recordings.

Conclusions:

• 2PP 3D printing offers a versatile and accessible platform for creating advanced in vitro neuronal models.
• This technology enhances experimental control and theoretical understanding of large-scale neural systems.
• The developed method facilitates neurotechnology and high-throughput neural data recording.