Carbon nanofiber yarn nerve scaffold

Abstract

Nerve scaffolds are described that include a tubular outer housing fabricated from a biocompatible polymer, within which are disposed a plurality of carbon nanofiber yarns. The carbon nanofiber yarns, which can be separated by distances roughly corresponding to an average nerve fiber diameter, provide surfaces on which nerve fibers can regrow. Because the proximate carbon nanofiber yarns can support individual nerve fibers, a nerve can be regenerated with a reduced likelihood of undesirable outcomes, such as nerve pain or reduced nerve function.

What is claimed is: 
     
         1 . A nerve scaffold comprising:
 a tube having a first end and a second end opposite the first end, the tube defining an interior region having a first diameter, the tube comprising a biocompatible material; and   a bundle of nanofiber yarns disposed within the interior region of the tube and extending from the first end of the tube to the second end of the tube, wherein,   the nanofiber yarns of the bundle of nanofiber yarns define a plurality of interstitial spaces between proximate nanofiber yarns that form at least one continuous pathway from the first end of the tube to the second end of the tube.   
     
     
         2 . The nerve scaffold of  claim 1 , wherein the nanofiber yarns are false twisted nanofiber yarns. 
     
     
         3 . The nerve scaffold of  claim 2 , wherein the nanofiber yarns are single ply false twisted nanofiber yarns. 
     
     
         4 . The nerve scaffold of  claim 2 , wherein a surface of the nanofiber yarns has an absence of surface topographic features greater than 1 μm above or below a surface of the nanofiber yarn. 
     
     
         5 . The nerve scaffold of  claim 2 , wherein a surface of the nanofiber yarns has surface topographic features less than 0.1 μm above or below a surface of the nanofiber yarn. 
     
     
         6 . The nerve scaffold of  claim 1 , wherein an average distance between proximate nanofiber yarns defining an interstitial space of the plurality of interstitial spaces is from 5 μm to 15 μm. 
     
     
         7 . The nerve scaffold of  claim 1 , wherein an average distance between proximate nanofiber yarns defining an interstitial space of the plurality of interstitial spaces is from 5 μm to 12 μm. 
     
     
         8 . The nerve scaffold of  claim 1 , wherein a mass of the plurality nanofiber yarns is from 2 mass % to 10 mass % of a total mass of the nerve scaffold. 
     
     
         9 . The nerve scaffold of  claim 1 , wherein a mass of the plurality nanofiber yarns is from 5 mass % to 20 mass % of a total mass of the nerve scaffold. 
     
     
         10 . The nerve scaffold of  claim 1 , wherein a mass of the plurality nanofiber yarns is from 15 mass % to 60 mass % of a total mass of the nerve scaffold. 
     
     
         11 . The nerve scaffold of  claim 1 , wherein the plurality of nanofiber yarns comprises from 1000 to 8000 nanofiber yarns. 
     
     
         12 . The nerve scaffold of  claim 1 , wherein a nanofiber yarn of the plurality of nanofiber yarns has a diameter of from 5 μm to 30 μm. 
     
     
         13 . The nerve scaffold of  claim 1 , wherein the yarns occupy between 1 and 5%, 1 and 10%, 1 and 20%, 1 and 30%, 1 and 40% or 1 and 50% of a volume of the tube. 
     
     
         14 . The nerve scaffold of  claim 1 , wherein the tube is comprised of a polymer. 
     
     
         15 . The nerve scaffold of  claim 1 , wherein the nanofiber yarns are comprised of carbon nanotubes. 
     
     
         16 . The nerve scaffold of  claim 15 , wherein the nanofiber yarns consist essentially of carbon nanotubes. 
     
     
         17 . The nerve scaffold of  claim 1 , wherein a plurality of interstitial spaces between proximate nanofiber yarns comprise a polymer, the polymer separating the nanofiber yarns. 
     
     
         18 . The nerve scaffold of  claim 1 , wherein the nanofiber yarns include a protein. 
     
     
         19 . The nerve scaffold of  claim 1 , wherein the first diameter of the interior region of the tube ranges from about 1.5 mm to about 15 mm. 
     
     
         20 . The nerve scaffold of  claim 1 , wherein the maximum weight ratio of the bundle of nanofiber yarns to the tube is about 0.65 to about 1.