Polymeric Nanocomposite Structures Based on Functionalized Graphene with Tunable Properties for Nervous Tissue Replacement

Abstract

Electroconductive scaffolds can be a promising approach to repair conductive tissues when natural healing fails. Recently, nerve tissue engineering constructs have been widely investigated due to the challenges in creating a structure with optimized physiochemical and mechanical properties close to the native tissue. The goal of the current study was to fabricate graphene-containing polycaprolactone/gelatin/polypyrrole (PCL/gelatin/PPy) and polycaprolactone/polyglycerol-sebacate/polypyrrole (PCL/PGS/PPy) with intrinsic electrical properties through an electrospinning process. The effect of graphene on the properties of PCL/gelatin/PPy and PCL/PGS/PPy were investigated. Results demonstrated that graphene incorporation remarkably modulated the physical and mechanical properties of the scaffolds such that the electrical conductivity increased from 0.1 to 3.9 ± 0.3 S m −1 (from 0 to 3 wt % graphene) and toughness was found to be 76 MPa (PCL/gelatin/PPy 3 wt % graphene) and 143.4 MPa (PCL/PGS/PPy 3 wt % graphene). Also, the elastic moduli of the scaffolds with 0, 1, and 2 wt % graphene were reported as 210, 300, and 340 kPa in the PCL/gelatin/PPy system and 72, 85, and 92 kPa for the PCL/PGS/PPy system. A cell viability study demonstrated the noncytotoxic nature of the resultant scaffolds. The sum of the results presented in this study suggests that both PCL/gelatin/PPy/graphene and PCL/PGS/PPy/graphene compositions could be promising biomaterials for a range of conductive tissue replacement or regeneration applications.

Biofabrication of a flexible and conductive 3D polymeric scaffold for neural tissue engineering applications; physical, chemical, mechanical, and biological evaluations

“…10,11 In our previous studies, PPy and functionalized graphene incorporation within a non-conductive system had a significant effect on both the electrical conductivity and the mechanical properties. 10,12 Furthermore, Chen et al fabricated a composite structure of carboxylic graphene oxide-polypyrrole/poly-l-lactic acid by electrochemical deposition method and confirmed its application in sciatic nerve repair. 13 Ascorbic acid or vitamin C is an essential micronutrient that has an important role in several important biological activities 14 such as protein, ligaments, and blood vessels formation also helps wounds and scar tissue to heal and preserve bone and cartilage tissue.…”

“…[7][8][9] PPy has shown great capability and potential in the field of tissue engineering because of the easy synthesis process, biocompatibility, and low cost. 10,11 In our previous studies, PPy and functionalized graphene incorporation within a non-conductive system had a significant effect on both the electrical conductivity and the mechanical properties. 10,12 Furthermore, Chen et al fabricated a composite structure of carboxylic graphene oxide-polypyrrole/poly-l-lactic acid by electrochemical deposition method and confirmed its application in sciatic nerve repair.…”

“…Recently, the utilization of conducting polypyrrole (PPy) for scaffold fabrication, tissue engineering, and drug delivery has increased 7–9 . PPy has shown great capability and potential in the field of tissue engineering because of the easy synthesis process, biocompatibility, and low cost 10,11 . In our previous studies, PPy and functionalized graphene incorporation within a non‐conductive system had a significant effect on both the electrical conductivity and the mechanical properties 10,12 .…”

“…17,18 Hence, here a blend of fairly strong biomaterial like PCL with an elastic polymer like gelatin is sued to develop a variety of biomaterials with a tunable range of architectural, mechanical and chemical elements that are suitable for nerve grafts application. In recent study, 10 the sum of results revealed that a system with a combination of multilayer graphene and conductive polymers, like polypyrrole, could produce superior electrical conductivity, biocompatibility and create suitable background for cell adhesion and proliferation and it could encourage electrical stimulation during nerve regeneration. 19,20 In addition, the multilayer graphene balances the mechanical weakness (composite reinforcement) of using polypyrrole while enhancing the electrical conductivity.…”

Gellan-Xanthan Hydrogel Conduits with Intraluminal Electrospun Nanofibers as Physical, Chemical and Therapeutic Cues for Peripheral Nerve Repair

“…Peripheral nerve tissue comprises a complex cellular arrangement, with electrical, mechanical and chemical properties [6]. A multifunctional repair system, featuring a variety of specialized components, is required to emulate the native architecture and function of nerve tissue for biomimetic appeal [7,8].…”