38e Fabrication of 3d Tissue Scaffolds in Tissue Engineering

David A. Wiist Jr., Chemical Engineering, Oklahoma State University, 16600 Kingsley Rd., Edmond, OK 73003

In tissue engineering, polymer-based scaffolds provide support and guidance required for cell growth and tissue regeneration. Specific properties like fiber thickness, pore size, and elasticity of the 3D matrices have yet to be intricately controlled for a better understanding of cellular preference. Here, a new 3D printing system has been used to fabricate chitosan-based tissue scaffolds for tissue engineering. Although other scaffold preparation methods are effective, the technique provides increased control and design of specific parameters in the porous scaffolds. Layer-by-layer, a computer guided Robocaster extrudes a polymer gel (chitosan dissolved in 0.5M acetic acid) through a small nozzle into a bath where the chitosan precipitates forming a solid 3D structure. The scaffold designer can specify the geometric blueprint and other parameters such as pore size. In addition, the efficient method provides increased consistency for the characterization of the scaffold's physical and mechanical properties. Thus far, scaffolds with fiber thickness as low as 200 microns have been successfully produced. Further decreases in nozzle size may provide insight into the cell's preference for optimal bioactivity and multiplication. With increasing control over the cellular microenvironment, characteristics of the perfect tissue scaffold become closer to discovery.