Si probe for infrared neural stimulation
In our work, we present a Michigan-type deep brain silicon optrode capable of delivering infrared light into the neural tissue. We proposed a fabrication method that is feasible to reduce the sidewall roughness significantly and is able to turn the substrate material into an infrared waveguide of sufficient efficiency for infrared neural stimulation. The advantage of our approach is that the fabrication process is fully compatible with that of functional neural microelectrodes.VIEW PROJECT
Immuneresponse to nanostructured neural probes
In our study, bioactive properties of Si nanopillars compared to microstructured Si surfaces were investigated after being implanted for eight weeks, in vivo. To form the randomly nanostructured surfaces, we utilise black polycrystalline silicon (poly-Si) thin film. The advantage of black poly-Si is that its production can be integrated into the fabrication scheme of Michigan type silicon neural microelectrodes. Our results suggest that surface topography can alter the effect of implantation regarding the preservation of neurons in a distance of 0–50 μm from the track. Nanostructuring the implant surface may be favourable for long-term applications as a larger neuronal density remains in the vicinity of a nanostructured surface and may provide better signal-to-noise ratio during electric recordings.
Polymer microECoG electrodes
Our surface electrodes have been efficiently used in animal studies on oscillatory connectivity and was also validated in pharmacological experiments. Our recent goal is to create novel, flexible, minimally invasive microsystems that are capable of high-resolution electrical monitoring of cortical activity and can be combined with other emerging neuroimaging techniques like functional magnetic resonance imaging, ultrafast ultrasound localization microscopy or two-photon microscopy.
Drug delivery microelectrodes
We have developed a silicon based miccroelectrode for simultaneous recording of cellular electrical activity and local drug delivery Fabrication scheme relies on the smart combination of Buried Channel Technology and Etching-Before-Grinding. Our micromachining concept provides injection, sampling and electrical recording — all integrated monolithically in a long and subsequently thinned silicon microelectrode. Feasibility of our microelectrode configuration has been demostrated in in vivo experiments.
In our work, the interaction of cell cultures and nanotextured surfaces is investigated as a model of implanted device surface and living tissue interaction. We have developed a robust, maskless nanostructuring method, which can be integrated into our neural biosensor fabrication process. GFPNE-4C cells are cultured on the nanostructured and platinized surfaces and are investigated by fluorescent microscopic imaging.VIEW PROJECT