Biomimetic Structured Porogen Freeform Fabrication System for Tissue Engineering

Drexel University, Philadelphia PA

Investigators

Abstract

The research objective of this project is to integrate biomaterials research, biomimetic modeling, solid freeform fabrication, systems and control, and tissue engineering in one intelligent system for structured, highly porous biomaterials, which will be applied to bone tissue engineering scaffolds. The manufacturing system is based on the following principles: (1) A computer-aided design model of bone is created based on images of computed tomography or magnetic resonance imaging and internal structure modeling using reverse engineering. (2) A specially designed sucrose material is used to build a structured porogen, a skeleton that has the negative structure of bone extra-cellular matrix voids, using Solid Freeform Fabrication technology. (3) A bio-composite of polymer and ceramic is cast into the sucrose negative skeleton and air-solidified. (4) The sucrose porogen is then removed using water; and the bio-composite scaffold is sintered at a low temperature to improve its mechanical integrity and strength. Biocompatibility will be tested in cell culture assays. Success in this project will enable tissue engineers to optimize mechanical, transport, material, and biological properties of bone tissue engineering scaffolds with a degree of structural control not currently available. Bone tissue engineering may offer a less painful alternative to traditional bone grafts in over 800,000 implants per year, with lower risk of infection. The new biomimetic structured porogen freeform fabrication system will also have application to scaffolds for other tissues, including vascularized tissue. Broader benefits include training of two Ph.D. students, new course modules on "Biomimetic Tissue Modeling and its Freeform Fabrication" and "Biomaterial Mechanical Property Measurement," and a biomaterials biocompatibility case study. The educational and research infrastructure can be enhanced by this interdisciplinary collaboration, and by development of new cross-disciplinary course modules for both College of Engineering and Biomedical Engineering School at Drexel University. The project will also be used in outreach workshops for local high school and community college students, including many underrepresented minority students.