Methods of making and bioelectronic applications of metalized graphene fibers

Abstract

The present disclosure provides methods of making and applying metalized graphene fibers in bioelectronics applications. For example, platinized graphene fibers may be used as an implantable conductive suture for neural and neuro-muscular interfaces in chronic applications. In some embodiments, an implantable electrode includes a multi-layer graphene-fiber core, an insulative coating surrounding the multi-layer graphene-fiber core, and a metal layer disposed between the multi-layer graphene-fiber core and the insulative coating.

What is claimed is: 
     
         1 . An implantable electrode comprising:
 a multi-layer graphene-fiber core;   a separating layer; and   an electrically conductive layer disposed at least in part between the multi-layer graphene-fiber core and the separating layer.   
     
     
         2 . The implantable electrode of  claim 1  wherein the separating layer is conductive. 
     
     
         3 . The implantable electrode of  claim 1  wherein the separating layer is non-conductive. 
     
     
         4 . The implantable electrode of  claim 1  wherein the separating layer is at least partially around the multi-layer graphene-fiber core. 
     
     
         5 . The implantable electrode of  claim 1  wherein the multi-layer graphene-fiber core has an exposed portion. 
     
     
         6 . The implantable electrode of  claim 3 , wherein the separating layer comprises Parylene-C. 
     
     
         7 . The implantable electrode of  claim 1 , wherein the electrically conductive layer is adjacent the multi-layer graphene-fiber core and the electrically conductive layer covers a surface portion of the graphene-fiber core with partial encapsulation of the multi-layer graphene-fiber core. 
     
     
         8 . The implantable electrode of  claim 1 , wherein the electrically conductive layer comprises at least one of platinum, iridium, iridium oxide, platinum-iridium, and titanium nitride. 
     
     
         9 . The implantable electrode of  claim 1 , wherein the multi-layer graphene-fiber core has a diameter about 10 μm to about 200 μm. 
     
     
         10 . A method for making an implantable electrode, the method comprising:
 forming a multi-layered graphene-fiber core using ordered graphene oxide sheets;   adding an electrically conductive layer to at least a portion of the multi-layered graphene-fiber core; and   applying a separation layer to the multi-layered graphene-fiber core and electrically conductive layer.   
     
     
         11 . The method of  claim 10  wherein forming comprises forming the multi-layered graphene-fiber core by performing an in-situ reduction of ordered graphene sheets. 
     
     
         12 . The method of  claim 11  wherein forming comprises forming the multi-layered graphene-fiber core by performing an in-situ reduction of ordered graphene sheets in a liquid crystalline. 
     
     
         13 . The method of  claim 10 , wherein the electrically conductive layer comprises at least one of platinum, iridium, iridium oxide, platinum-iridium, and titanium nitride. 
     
     
         14 . The method of  claim 10 , wherein the electrically conductive layer has thickness in the range between about 10 nm to about 500 nm. 
     
     
         15 . The method of  claim 10 , wherein the separation layer comprises Parylene-C.