Stretchable Low Impedance Electrodes for Bioelectronic Recording from Small Peripheral Nerves

Monitoring of bioelectric signals in peripheral sympathetic nerves of small animal models is crucial to gain understanding of how the autonomic nervous system controls specific body functions in health and disease. Advances in the understanding of autonomic nerves function depend on the availability of low-invasive electrodes for the chronic recording of nerve activity in conscious animals. Here we report a highly stretchable low-impedance electrode realized by microcracked gold films as metallic conductors covered with electrodeposited, stretchable conducting polymer composite to facilitate ion-to-electron exchange. The conducting polymer composite based on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) obtains its adhesive, low-impedance properties by controlling thickness, plasticizer content and deposition conditions. Atomic Force Microscopy measurements under strain show that the optimized conducting polymer coating is compliant with the micro-crack mechanics of the underlying Au-layer, necessary to absorb the tensile deformation when the electrodes are stretched. In conclusion, we demonstrate the applicability of the proposed stretchable electrodes by performing in vivo high quality recordings of renal sympathetic nerve activity in conscious rats.