Neuronal cell culture technologies are progressing from 2D culture plate confinements with random network configurations to bio-patterned networks with controlled topologies and to 3D configurations. These techniques provide new opportunities for functional in-vitro studies as well as alternative perspectives for brain tissue implantation.

Here, we report recent results achieved in combining these cell culture technologies with micro-electrode arrays (MEAs) for network electrophysiological investigations. Interestingly, this device was proved to provide a high statistical significance of network activity parameters and to enable detailed localization and tracking of spatiotemporal activity patterns.

We report on the use of an improved bio-patterning technique enabling long-term growth of topologically defined neuronal networks prepared from E17 rat primary hippocampal cells. By using a microcontac printing (mCP) technique we investigate whether the functional network features are modifyied by an imposed network topology. Futhermore, neuronal cultures were also prepared on laser-etched Kapton membranes acting as cell culture substrates to sustain 3D neuronal growth. In this case, a second neuronal culture was used to induce vertical growth of neuronal projections through the membrane pores and to achieve a 3D-growth of neuronal projections. Our results demonstrate how these membrane cultures can be coupled with high-resoluiton MEAs for functional electrophysiological measurements.

In perspective, bio-patterning and 3D neuronal growth represent technologies to direct and organize neuronal network models. The combination with high-resolution MEAs will allow the detailed study of complex functional circuitries.