Graphene Oxide-Based Biocompatible 3D Mesh with a Tunable Porosity and Tensility for Cell Culture

One of the major challenges associated with modeling the influence of the cellular microenvironment on cell growth and differentiation is finding suitable substrates for growing the cells in a manner that recapitulates the cell-cell and cell-microenvironmental interactions in vitro. As one approach to address this challenge, we have developed graphene oxide (GO)-3D mesh with tunable hardness and porosity for application in cell culture systems. The synthetic method of GO-3D mesh is simple, easily reproducible, and low cost. The foundation of the method is the combination of poly(ethylene)(glycol) (PEG) and GO together with a salt-leaching approach (NaCl) in addition to a controlled application of heat during the synthetic process to tailor the mechanical properties, porosity, and pore-size distribution of the resulting GO-3D mesh. With this methodology, the hydrogel formed by PEG and GO generates a microporous mesh in the presence of the NaCl, leading to the formation of a stable 3D scaffold after extensive heating and washing. Varying the ratio of NaCl to GO controls porosity, pore size, and pore connectivity for the GO-3D mesh. When the porosity is less than 90%, with an increasing ratio of NaCl to GO, the number of pores increases with good interconnectivity. The 3D-mesh showed excellent biocompatibility with vascular cells which can take on a morphology comparable to that observed in vessels in vivo. Cell proliferation and gene expression can be determined from cells grown on the GO-3D scaffold, providing a valuable tool for investigating cell-microenvironmental changes. The GO-3D mesh described results from the synergy of the combined chemical properties of the PEG and GO with the salt-leaching methodology to generate a unique and flexible mesh that can be modified and optimized for a variety of in vitro applications.