(252g) The Effect of Nanoscale Structure on Degradable Polymer Tissue Scaffolds

Tissue scaffolds are materials that provide structure capable of supporting cell growth for tissue engineering applications. Polymers are excellent materials for these scaffolds because of the broad range of chemistries and material properties available. The ideal scaffold properties are application specific and must be tailored for individual cell and tissue types, making polymeric materials especially viable. In this research, we examine the effect of nanoscale structure on the effectiveness of degradable polymer systems for retinal tissue engineering. Poly(glycerol sebacate) diacrylate, poly(caprolactone) diacrylate, and poly(ethylene glycol)-poly(lactic acid)-poly(ethylene glycol) diacrylate were identified as degradable materials with desirable characteristics for retinal tissue scaffolds. Through photopolymerization of lyotropic liquid crystal (LLC) templates and the use of two photon polymerization, nanostructure was imparted to the polymer scaffolds. LLC templating involves the self-assembly of surfactant molecules in a solvent into ordered mesophases. Through the addition of monomer and initiator, photopolymerization can kinetically trap the ordered structure of the LLCs. As another method of designing scaffolds, two photon polymerization was used to print small-scale structures with high resolution in three dimensions. The structure of the materials was determined through small-angle x-ray scattering (SAXS) and scanning electron microscopy (SEM) and the mechanical properties of the materials were determined via dynamic mechanical analysis (DMA). Induced pluripotent stem cells obtained from mice were cultured on the polymer scaffolds and cell growth was used to determine the effects of polymer chemistry, mechanical properties, and the presence of nanoscale structure on the effectiveness of these polymer scaffolds for retinal tissue engineering.