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bioRxiv · 10.1101/2021.08.21.457239

Electrical activity recorded from the spinal cord in freely moving rats using a subdural bioelectronic implant

Harland, B. C.·Aqrawe, Z.·Vomero, M.·Boehler, C.·Raos, B.·Asplund, M.·O'Carroll, S.·Svirskis, D.
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Abstract

Bioelectronic devices have found use at the interface with neural tissue to investigate and treat nervous system disorders. Here, we present the development and characterization of a thin flexible bioelectronic implant inserted over the thoracic spinal cord in rats directly in contact with the spinal cord. There was no negative impact on hind-limb functionality nor any change in the volume or shape of the spinal cord. The bioelectronic implant was maintained in rats for a period of 3 months. We present the first subdural recordings of spinal cord activity in freely moving animals. Recordings contained multiple distinct voltage waveform shapes that were typically between 1 - 6 mV and lasted between 0.1 and 1 seconds. In the future, this implant will facilitate the identification of biomarkers in spinal cord injury and recovery, while enabling the delivery of localized treatments.

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Harland, B. C., Aqrawe, Z., Vomero, M., Boehler, C., Raos, B., Asplund, M., O'Carroll, S., Svirskis, D.. 2021-08-23. Electrical activity recorded from the spinal cord in freely moving rats using a subdural bioelectronic implant. https://doi.org/10.1101/2021.08.21.457239

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