Ultra-low percolation threshold POSS-PCL/graphene electrically conductive polymer: Neural tissue engineering...

An ultra-low percolation threshold electrically conductive polymer nanocomposite incorporating graphene into a polyhedral oligomeric silsesquioxane polycaprolactone (POSS-PCL/graphene) is described in this paper. Multilayer graphene flakes were homogeneously dispersed into POSS-PCL at 0.08, 0.4, 0.8, 1.6, and 4.0 wt% concentrations. The impedance spectroscopy of 0.08 wt% and higher concentration of graphene in POSS-PCL represented major improvement in conductivity over pristine POSS-PCL. The percolation threshold occurred at 0.08 wt% graphene concentration, and at 4.0 wt% the electrical conductivity exceeded 10^-4 Scm^-1. Furthermore, the chemical, morphological, and mechanical of the POSS-PCL/graphene with various graphene concentrations were investigated. Finally, neural cells cultured on all POSS-PCL/graphene constructs indicated higher metabolic activity and cell proliferation in comparison with pristine POSS-PCL. Herein, we demonstrate a method of developing a neural-compatible and electrically conductive polymer nanocomposite that could potentially function as a neural tissue engineered platform technology for neurological and neurosurgical applications.