Fabrication of Architectured Biomaterials by Multilayer Co-Extrusion and Additive Manufacturing

Tissue engineering benefits from advances in 3D printing and multi-material assembly to attain certain functional benefits over existing man-made materials. Multilayered tissue engineering constructs might unlock a unique combination of properties, but their fabrication remains challenging. Herein, a facile process is reported to manufacture biomaterials with an engineered multilayer architecture, via a combination of co-extrusion and 3D printing. Polymer filaments containing 5, 17, or 129 alternating layers of poly(lactic acid)/thermoplastic polyurethane (PLA/TPU) are produced, and explored for their use in fused deposition modeling (FDM) to fabricate scaffolds for cardiomyocyte culture. The co-extruded filaments exhibit a layered architecture in their cross-section with a continuous interface, and the integrity and alignment of the layers are preserved after 3D printing. The 17 alternating layers PLA/TPU composites exhibit excellent mechanical properties. It is envisaged that the multilayered architecture of the fabricated scaffolds can be beneficial for aligning cardiomyocytes in culture. It is found that the 17 alternating layers PLA/TPU significantly improve cardiomyocyte morphology and functionality compared to single phase materials. It is believed that this biomaterials fabrication scheme, combining a top-down and bottom-up approach, offers tremendous flexibility in producing a broad class of novel-architectured materials with tunable structural design for tissue engineering applications and beyond.