Development of Multi-Layer Scaffolds Based on Artificial Configuration

In this work, we propose a multi-layered scaffold made of elastic biodegradable polymer PLCL [1] by salt leaching method [2], which has high porosity at inner layer and high stiffness in outer layer. Before implanting to a damaged position of a patient, scaffolds should be coated with human umbilical vein endothelial cells (HUVECs). (Porous structure is also served as a pathway of sufficient nutrients and oxygen). This inner layer has porosity as means to culture HUVECs on itself, and outer layer has stiffness as means to maintain shape of scaffolds against blood flow as that of blood vessels does. These inner and outer layers were reproduced also as means of intimal layer and internal elastic lamina in human blood vessel especially muscular artery respectively. It was also verified that this fabrication method can be applied to fabricate tri-layered tubular artificial blood vessel scaffold by SEM. Mechanical characterization and porosity of bi-layered scaffolds were evaluated by tensile test and image processing respectively. These parameters were confirmed that can be controllable by adjusting concentration of NaCl for inner layer used in salt leaching method. HUVECs were cultured on the porous structure of bi-layered scaffolds, and the scaffold's biocompatibility was confirmed by viability of cells. Results obtained from these experiments shows we can propose artificial blood vessel scaffold, which has optimal porosity and mechanical strength, not to induce blood clot, intimal hypertrophy and so on in patient's body.