Fabrication of Biomimetic Scaffolds With Well-Defined Pore Geometry by Fused Deposition Modeling

It is well established that the pore size and distribution affect the rate of cell migration and the extent of extracellular matrix formation. The objective of this work was to develop a process for fabrication of biodegradable and shape-specific polymeric scaffolds with well-defined pore geometry, functionalized with covalently attached bioactive peptides, for applications in tissue regeneration. We have used the Fused Deposition Modeling (FDM) RP technology to fabricate degradable and functional scaffolds with well-defined pore geometry. Computer aided design (CAD) using SolidWorks was used to create models of the cubic orthogonal geometry. The models were used to create the machine codes necessary to build the scaffolds with FDM with wax as the build material. A novel biodegradable in-situ crosslinkable macromer, poly(lactide-co-glycolide fumarate) or PLGF, mixed with reactive functional peptides was infused in the scaffold and allowed to crosslink. The scaffold was then immersed in a hydrocarbon solvent to remove the wax, leaving just the PLGF behind as the support material dissolved. The pore morphology of the PLGF scaffold was imaged with micro-computed tomography and scanning electron microscopy. Cellular function in the PLFG scaffolds with well-defined pore geometry was studied with bone marrow stromal cells isolated from rats. Results demonstrate that the scaffolds support homogeneous formation of mineralized tissue.