Fabrication and Biocompatibility of Electroconductive Silk Fibroin/PEDOT: PSS Composites for Corneal Epithelial Regeneration.

The aim of this study was to develop matrices that can support human corneal epithelial cells and innervation by incorporating a conducting polymer, poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate) (PEDOT:PSS), into silk fibroin (SF). Polyvinyl alcohol (PVA) was used as a crosslinking agent to enhance the mechanical properties of the matrices. The impact of PEDOT:PSS on the materials' physical properties and cellular responses was examined. The electrical impedance of matrices decreased with increasing concentration of PEDOT:PSS suggesting improved electroconductivity. However, light transmittance also decreased with increasing PEDOT:PSS. Young's modulus was unaffected by PEDOT:PSS but was increased by PVA. The viability of corneal epithelial cell on the matrices was unaffected by the incorporation of PEDOT:PSS except at the highest concentration tested 0.3% (w/v), which led to a cytotoxic response. These findings suggest that SF/PEDOT:PSS with a PEDOT:PSS concentration of 0.1-0.2% would be a suitable biomaterial for epithelium regeneration.