Design, Fabrication, and Characterization of Allograft Regenerative Peripheral-Nerve Interfaces (A-RPNI)

Although regenerative peripheral-nerve interfaces (RPNIs) have shown promise in restoring neural connectivity, existing approaches often suffer from under sampling nerve activity. Here, we report the design, fabrication, and in vitro characterization of an allograft regenerative peripheral-nerve interface (A-RPNI)—the first to embed a dense three-dimensional microelectrode array into a decellularized nerve allograft. In contrast to our prior Tissue-Engineered Electronic Nerve-Interface (TEENI) approach, which employed templated hydrogels or empty conduits, the A-RPNI integrates a stingray-shaped thread-set design directly into the native extracellular matrix (ECM) scaffold of the allograft. This new design enables more channels to be integrated into a dense 3-D configuration with improved electrode-positioning precise while not increasing the lead, packaging, nor surgical complexity. We anticipate that leveraging the natural ECM architecture of the allograft will enhance axonal regeneration around the 3-D microelectrode array, ultimately providing a more effective platform for peripheral-nerve interfacing.