Additive manufacturing of 3D networks based on poly(lactic acid) and amine functionalized graphene oxide as a platform for scaffolds

In the present study, 3D networks were printed using the fused deposition modeling (FDM) technique. The purpose was investigate the printability of graphene oxide (GO)-based composites for potential bone tissue engineering applications. Poly(lactic acid) (PLA) filaments containing GO and amine functionalized GO (N-GO) were produced by melt extrusion and employed to print 3D networks. The cytotoxicity, morphological, rheological, and thermal behavior of the samples were compared. The morphological, rheological, and wettability analyses indicated an improvement in dispersion of GO throughout the matrix of PLA when GO was amine functionalized. The viscoelastic and flow properties, as determined by rheology, indicated that printed PLA samples containing freeze-dried GO had lower viscosity than other composites, with a viscosity of 59.4 (Pa s), a decrease of nine times when compared with pure PLA, while the PLA containing N-GO presented an improved viscoelastic interaction. PLA contact angle (108 degrees ) decreased by 87 degrees and 84 degrees for N-GO and GO, respectively. The thermal analyses depicted that the incorporation of freeze-dried GO and N-GO had no effect on the crystallinity or thermal transitions of PLA matrix, maintaining its thermal stability. Finally, the cytotoxicity analysis indicated that the composites were not toxic throughout the cell culture assay and were found to promote cell viability, especially for the PLA/N-GO network. Thus, these results revealed a vast horizon toward the use of GO/biodegradable polymers as platforms to print 3D networks to be applied as scaffolds.