Development of a bioink for 3D bioprinting for the development of 3D constructs for biomedical applications

Abstract

The fabrication of 3D constructs using 3D bioprinting techniques aims to overcome some of the weakness curently experienced by the conventional scaffold-­‐based tissue regeneration approach. One of the most challenging aspects in fabricating 3D constructs in tissue engineering is the design of a construct will relevant size that will allow the attachment and proliferation of cells while having excellent mechanical properties. Hydrogel-­‐based materials are currently the suitable materials given their high biocompatability. However, they faced poor mechanical properties. Self-­‐assembling peptide hydrogels, such as the one used in the current work, are a promising biomaterial given their spontaneous formation of a nanofibrous netowrk, which mimicks the extraceullar matrix and support cell growth, differentiation, and proliferation. Here, a commercial self-­‐assembling peptide hydrogel/bioink, which for confidential reason, its name cannot be provided, was characterized. First, the optimal concentration of the formulation was obtained until printing a filament in air was possible.In addition, the optimal printing parameters were found. Furthermore, the printing fidelity of the bioink was characterized by analyzing its strand and porosity width and comparing that to the theoretical one in the scaffold design. In addition, the cell viability of encapsulated human-­‐adipose mesenchymal stem cells was analyzed by performing a live/dead assay on different concentration before and after printing. Moreover, a comparison between 2D vs 3D was performed by analyzing the cell’s viability when the cells are encapsulated inside the bioink and printed versus 3D printing the scaffold without the cells and adding the cells on top (2D cell culture) after printing. Finally, proliferation studies were performed on the 3D printed scaffolds were cells were added on top 2D. To conclude, an environment and economical analysis of the project was performed.