Fabrication and Characterization of Porous Polyurethane Scaffold for Application in the Field of Tissue Engineering

In tissue engineering, a highly porous artificial extracellular matrix or scaffold is required to accommodate mammalian cells and guide their growth and tissue regeneration in three dimensions.Successful tissue engineering of soft tissue largely depends on synthetic scaffolds that support the survival, proliferation and differentiation of seeded cells.In this investigation of the use of L-tyrosine based polyurethane in soft tissue engineering, three dimensional and 90% porous biodegradable polyurethane scaffolds with highly interconnected pore structure were fabricated by solvent casting and particulate leaching technique.Scaffolds were fabricated using ground and sieved sodium chloride particles.The grinding and sieving of sodium chloride resulted in particulates of uniform particle sizes but irregular shapes.Biodegradable L-tyrosine polyurethane scaffolds fabricated from these particulates had highly interconnected channels and the pores size that could allow cellular infiltration and nutrient delivery.The scaffolds had anisotropic pore structure with pore diameter ranging from 144-250 μm in diameter.Studies were conducted to investigate the effect of sodium chloride particulates on scaffold porosity and mean pore diameter.The study showed that scaffolds made using solvent casting and particulate leaching techniques demonstrated independent control of porosity and mean pore diameter of scaffold.Compression testing demonstrated mechanical anisotropy concomitant with the direction of the macro-pores.The porous architecture of these scaffolds reflected the CHAPTER I