Physical and electrical characterization of TexasPEG: An electrically conductive neuronal scaffold

William K A Sikkema; Andrew B Metzger; Tuo Wang; James M Tour

doi:10.4103/sni.sni_361_16

Physical and electrical characterization of TexasPEG: An electrically conductive neuronal scaffold

Surg Neurol Int. 2017 May 26:8:84. doi: 10.4103/sni.sni_361_16. eCollection 2017.

Authors

William K A Sikkema¹, Andrew B Metzger¹, Tuo Wang¹, James M Tour^{1

2

3}

Affiliations

¹ Department of Chemistry, Rice University, Houston, Texas, USA.
² The NanoCarbon Center, Rice University, Houston, Texas, USA.
³ Department of Material Science and Nanoengineering, Rice University, Houston, Texas, USA.

Abstract

Background: Graphene and its derivatives have been shown to be biocompatible and electrically active materials upon which neurons readily grow. The fusogen poly(ethylene glycol) (PEG) has been shown to improve outcomes after cervical and dorsal spinal cord transection. The long and narrow PEGylated graphene nanoribbon stacks (PEG-GNRs) with their 5 μm × 200 nm × 10 nm dimensions can provide a scaffold upon which neurons can grow and fuse. We disclose here the extensive characterization data for the PEG-GNRs.

Methods: PEG-GNRs were chemically synthesized and chemically and electrically characterized.

Results: The average aspect ratio of the PEG-GNRs was determined to be ~85, which corresponds to a critical percolation value (the point where insulating material becomes conductive by addition of conductive particles) of 1%. However, there was not a sharp increase in AC conductivity at frequencies relevant to action potentials.

Conclusion: A robust characterization of PEG-GNRs is discussed, though the precise origin of efficacy in improving outcomes following spinal cord transection is not known.

Keywords: Fusogen; PEG; graphene; nanoribbons.