Posters

COMPUTATIONAL APPROACHES FOR MODELING OPTOELECTRONIC STIMULATION

Sara Stoppacher1*, Mathias Polz1*, Christian Baumgartner1, Marta Nowakowska2, Susanne Scheruebel3, Muammer Ücal2, Karin Kornmüller1, Rainer Schindl4, Tony Schmidt4, Niroj Shrestha4, Theresa Rienmüller1

1Institute of Health Care Engineering with European Testing Center of Medical Devices, Graz University of Technology, Austria; 2Department of Neurosurgery, Medical University of Graz, Graz, 8010 Austria; 3Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic; 4Gottfried Schatz Research Center – Biophysics, Medical University of Graz, Graz, 8010 Austria

Photocapacitive electrodes are very promising devices for the external stimulation of excitable cells and tissue. Computational models can be used to elucidate and explain the mechanism of the cell-electrode interface in in-vitro experiments. The well-known Stern model is used for the characterization of the double-layer formation on top of the photocapacitive electrode under (quasi) static conditions. A modified two-domain Fromherz model is exploited to describe the photocap-cell coupling as well as the interaction with involved control and measurement systems like the patch clamp technique. Electrophysiological cell models complete the entire electrode-cell system. Finite element models are created for the visualization of the electric field distributions. The parametrization and evaluation of the models bases on detailed measurements. To conclude, single-cell models reveal an explanation of ionic current responses in the interaction. A holistic overview of photocapacitive stimulation derived from the combination of all available models allows important experimental parameters to be defined to optimize the cell response.

* Equally contributed

Presenting author e-mail address: sara.stoppacher@tugraz.at