title: Design of barrier coatings on kink-resistant peripheral nerve conduits.
abstract: Here, we report on the design of braided peripheral nerve conduits with barrier coatings. Braiding of extruded polymer fibers generates nerve conduits with excellent mechanical properties, high flexibility, and significant kink-resistance. However, braiding also results in variable levels of porosity in the conduit wall, which can lead to the infiltration of fibrous tissue into the interior of the conduit. This problem can be controlled by the application of secondary barrier coatings. Using a critical size defect in a rat sciatic nerve model, the importance of controlling the porosity of the nerve conduit walls was explored. Braided conduits without barrier coatings allowed cellular infiltration that limited nerve recovery. Several types of secondary barrier coatings were tested in animal studies, including (1) electrospinning a layer of polymer fibers onto the surface of the conduit and (2) coating the conduit with a cross-linked hyaluronic acid-based hydrogel. Sixteen weeks after implantation, hyaluronic acid-coated conduits had higher axonal density, displayed higher muscle weight, and better electrophysiological signal recovery than uncoated conduits or conduits having an electrospun layer of polymer fibers. This study indicates that braiding is a promising method of fabrication to improve the mechanical properties of peripheral nerve conduits and demonstrates the need to control the porosity of the conduit wall to optimize functional nerve recovery.
authors.affiliation: New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Basak Acan
authors.initials: BA
authors.lastname: Clements
authors.affiliation: School of Pharmacy, University of Wyoming, Laramie, WY, USA.
authors.forename: Jared
authors.initials: J
authors.lastname: Bushman
authors.affiliation: New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: N Sanjeeva
authors.initials: NS
authors.lastname: Murthy
authors.affiliation: New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Mindy
authors.initials: M
authors.lastname: Ezra
authors.affiliation: Kanbar College of Design, Engineering and Commerce, Philadelphia University, Philadelphia, PA, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Pastore
authors.affiliation: New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ, USA; Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Joachim
authors.initials: J
authors.lastname: Kohn
keywords: Peripheral nerve; braided conduit; braiding; hyaluronic acid; nerve conduit; nerve regeneration; porosity