Indirect fabrication of tissue engineering scaffolds using rapid prototyping and a foaming process

The proliferation of cells on scaffolds is critical to the success of most tissue engineering strategies. However, most conventionally fabricated scaffolds are thick foam structures with random porosity that facilitates the proliferation of cells only at the periphery of the scaffold. Nutrient exchange to the scaffold interior becomes obstructed and cell growth is restricted once the cells on the periphery start growing into multi-layers. In the present study, scaffolds with a three dimensional (3D) interconnected network of channels were fabricated to overcome the diffusion barrier. In addition, a scaffold material with the ability to foam was used to generate porosity within the 3D scaffold. By controlling the foaming process, the pore size range of the resulting scaffold can be tailored. This article describes the developmental process of an indirect fabrication approach which involves the application of Rapid Proto-typing (RP) technology as well as the use of a foaming material to produce highly and uniformly porous scaffolds with complex channel architectures. Finally, the possible toxicity of the fabricated scaffolds as a result of the multiple processing steps is assessed.