Direct-Deposition and Multiple Materials Integration of Tissue Engineering Scaffolds

High-aspect-ratio three-dimensional structures using biocompatible materials are critical for tissue engineering applications. This study develops a multi-nozzle direct-write approach to construct tissue engineering scaffolds with complex three-dimensional structures utilizing polymeric materials. This approach provides the capability to fabricate three dimensional scaffolds by depositing biocompatible UV-curable polymeric material and thermoplastic material (paraffin wax) layer-by-layer, which respectively are used as structural material and supporting material that will be removed later on. The designed structure is built by selectively extruding drops and/or filament through a set of syringes that host different functional materials, following a layer-by-layer sequence. The location of the deposition is precisely controlled by a high precision three-dimensional translational stage. After different structural/functional materials and the supporting material are deposited with predesigned pattern, the supporting material is removed by using appropriate chemical solvent which will not affect physical and chemical properties of the designed structure. The mechanical property of the structure, the equilibrium modulus and dynamic stiffness, can be engineered by designing different pore size for the scaffold. The multi-nozzle based direct writing approach provides a practical solution to build scaffolds for tissue engineering and integrate multiple functional materials together into a single scaffold structure.