In Vitro Platform for Basic Testing of Micro- and Nanoelectrodes Intended for Chronic Implantation

Microelectrodes today and nanoelectrodes tomorrow further studies in fields of science such as neurobiology and electrophysiology, and are already in use as neural prosthetics. When electronic devices are used in biomedicine, especially when needed for chronic implantation, their ongoing downscaling is largely motivated by two aspects: biocompatibility and specificity. It has been shown that downscaling is a way to significantly decrease the damage done by such devices. In the research and development of new, complex devices, these need be continuously evaluated in various ways. In vivo experiments are one necessary part, and in vitro cell cultures are far from a complete substitute to an entire animal, but they constitute a very useful model nonetheless. There are three main drawbacks to in vivo testing: the cost, the complexity of the living organism – which can be an obstacle in routine tests – and animal suffering – the main reason why animal testing should only be used if there is no other sufficient option. Consequently, cell cultures can be much more appropriate in some instances. The aim of this project was to set up a quick-stop in vitro test station at which different electrode designs can be tested against one another. An existing setup originally assembled for patch clamp experiments was used with cell cultures chosen for other experiments primarily. PC12 cells and later mouse cortical neural stem cells were stimulated with KCl to produce action potentials. For PC12 cells no action potentials were registered, and for the cortical stem cells the consistency sought was not achieved. It is possible that this setup, using cortical stem cells, can achieve the intended practical use, but this project cannot assess this finally