4th Annual Mountain West
Biomedical Engineering Conference

A major challenge in the field of cardiac tissue engineering is oxygen and nutrient transport in scaffolds thicker than 150 microns. Perfused scaffolds have shown potential for allowing development of thicker, more clinically relevant tissue engineering constructs. Moreover, scaffolds with architectural cues have been shown to influence cellular alignment, which is an import feature when developing tissue such as cardiac tissue where cellular orientation has been shown to be paramount for construct function. We report here a method for fabricating laminated tissue engineering scaffolds of aligned microstructure with perfusion channels. Scaffolds were fabricated from polyether polyurethane using a sprayed phase separation method. Post spray elongation was used to generate an aligned microstructure within the scaffolds. Tensile testing and SEM visualization were used to assess scaffold anisotropy. To generate thick scaffolds, individual plies were laminated together. Hollow fibers (Ø 370 μm) were placed between plies during the lamination process to generate perfusion channels. After the scaffolds dried, the hollow fibers were removed leaving a continuous channel through the scaffold. Further, these scaffolds were placed into a custom built bioreactor and cyclically strained. Convective nutrient transport was modeled based on the measured Poisson’s ratio of the scaffold, strain, and size of perfusion channels. It was calculated that for each strain cycle, 12% of the media in the channel was exchanged with external media. Future work includes assessing cell distribution within scaffolds with and without perfusion channels and varying degrees of cyclic strain.