Towards non-wettable neural electrodes for a minimized foreign body reaction.

Functionality of neural implants can be seriously impaired by scarring during the foreign body reaction (FBR). Tailoring of the material-tissue interface is supposed to modulate part of the FBR. Surface structures might physically modulate the foreign body reaction in the acute phase directly after implantation. This work focuses on fabrication and characterization of bioinspired microtextures comprising reentrant cavities with non-wettable surface characteristics. The Selected microstructure patterns were fabricated using direct laser writing and were characterized by means of contact angle measurements and immersion tests. Clinical Relevance-Suggested by the outcome of this study, the proposed surface characteristics in neural interface can impact the wetting properties of the interface, hence, influence the interaction between the body fluid with the surface of the neural implant. Future studies should address the impact of the suggested design criterion and their applicability in improving the long-term stability of neural implants.

Laser-Induced Carbon Pyrolysis of Electrodes for Neural Interface Systems.

The objective of this work is to produce a laser- fabricated polymer-metal-polymer electrode with the merit of a carbon-based coating as the active site. A 10 µm-thick layer of parylene-C is used serving as the insulation layer in which the active site is locally laser-pyrolyzed. Our preliminary results show that the proposed method is promising in terms of fabrication feasibility and desired electrochemical capabilities.