Fabrication of hydrogel scaffolds using rapid prototyping for soft tissue engineering

Three-dimensional (3-D) scaffolds require an interconnected structure with controllable and reproducible porosity to guide cell growth and tissue regeneration for tissue engineering and regenerative medicine. In this study, a cell-plotting system was developed using a solid freeform fabrication (SFF) technique and fabricated hydrogel scaffolds with an interconnected pore structure using various hydrogels such as agarose, PluronicA (R) F127, and alginate. The plotting process was characterized using discharge data and the thicknesses of the hydrogel lines. Alginate was plotted under a range of pressures, with optimal plotting at 120 and 220 kPa for 2% and 4% alginate, respectively. The 4% alginate hydrogel was more stable in the plotting process than the 2% alginate. Cells seeded in the hydrogel showed good cell viability in a preliminary in vitro test. 3-D hydrogel scaffolds were produced successfully for soft tissue engineering applications.