Fabrication of Poly(urethane urea)-based Scaffolds for Bone Tissue Engineering by a Combined Strategy of Using Compression Moulding and Particulate Leaching Methods

Afacile procedure for fabrication of a poly(urethane urea)-based porous scaffold with proper porosity, pore size and mechanical strength for bone tissue engineering is reported in this work. For this purpose, sodium chloride (inorganic porogen) and polyethylene glycol (polymeric porogen) in particulate form with pre-defined mesh sizes were mixed with the polymer and subjected to compression moulding process under optimum condition. Leaching out the impregnated porogen particles by soaking in water (as a safe solvent) led to the final scaffold with desired morphology. The porogen ratios and contents were verified in relation to pore morphology and mechanical properties of the scaffolds. Porosity and pore size of the scaffolds were independently controlled by the ratio and the particle size of the added porogen. An increase in pore interconnectivity was observed as the sodium chloride/polyethylene glycol ratio was increased. Scaffolds with a total porogen content of 80-85 (wt%) displayed acceptable mechanical properties for bone tissue engineering applications. Our results revealed that a highly porous three-dimensional scaffold ( 85 (v%)) with a well interconnected porous structure could be achieved by this combinatory process. The scaffold with a NaCl/polyethylene glycol ratio of 60/25 exhibited a suitable morphology for osteoblast cells attachment and growth