Contract: $99,990 - National Science Foundation - Jun. 30, 2009
60% voted satisfied - 40% voted not satisfied - 5 vote(s) cast
Award Description: This Small Business Innovation Research project submitted by MO-SCI Corp. in collaboration with the Missouri University of Science & Technology (Missouri S&T) proposes to develop novel prototype bone scaffolds that are synergistic with the natural bone tissue regeneration process. Bare and bioresorbable polymer coated bioactive glass will be used as powder feedstock to a rapid prototyping selective laser sintering (SLS) machine to fabricate the proposed resorbable bone tissue scaffolds. The expected outcome is to develop an SLS technique for fabricating 3-D scaffolds (duplicating bone parts) using bioactive glass 13-93 powder, <75 ìm particle size. The scaffolds should have large porosity (between 50 and 80%) and relative large pore and ?channel size (100 to 50 ìm diameter) to allow vascularization. This is known from current data at Missouri S&T by Prof. Delbert Day and PhD student Steven Jung from parallel projects. They have used 3-D scaffolds made with 13-93 glass fibers, 300 ìm diameter, in random orientation, which shows that vascularization has been achieved and promoted proving the usefulness of the scaffold. The advantages of proposed SLS-scaffolds include manufacturing contour shapes as needed, controlling porosity, and the possibility of making scaffolds with porosity gradients or structural gradients. The 3-D scaffold fabrication is based on coating the bioactive glass powder with thermoplastics, which melt when a computer controlled laser beam scans to heat the powders. The thermoplastic acts like a binder to ?glue? the particles together to form a thin solid layer structure. After one layer is finished, according to the computer generated slice pattern from a computer aided design (CAD) model, the second layer begins. The final 3-D component, fabricated by continuous deposition of layers is stacked together. After SLS processing, the binder is removed by pyrolysis and the component is sintered to consolidate the structural sections of the scaffold. Additionally, SLS-tests have also been done by treating 13-93 glass powder without polymer binder. The results of the present contract include the fabrication of scaffold prototype sample 25 x 25 x 2 mm height with bioactive glass 13-93, as powder (<75 ìm particle size) with a 25 w CO2 laser and a SLS located at Missouri S&T. The scaffold prototypes have open porosity above 50% and pore size below 500 ìm. Further tests are needed to increase the structural integrity of the scaffold prototypes for the biological tests. Future work will include use of stearic acid as binder or glass beads as powder feedstock. The deliverables at the end of the contract are 3-D scaffolds in shapes (cubes or cylinders) of controlled porosity. Bioactivity will be compared to the results obtained at Missouri S&T from scaffolds made with fibers instead of powders. The unit of measure for this bioactivity is to show that vascularization can be provided with the new 3-D SLS-made scaffolds.
Project Description: The services performed by the prime contractor include (1) designing 3-D scaffolds that can be used as bone scaffolds using a SLS machine located at Missouri S&T, (2) manufacturing and providing bioactive glass 1393 feedstock for the SLS machine, (3) analyzing data and partial reports (internal and from Missouri S&T), and (4) supervising the whole project and the communication and activities with subcontractor (Missouri S&T).
Jobs Summary: A graduate student (Master in the Mechanical Engineering Department) has been hired 0.25 FTE at the Missouri University of Science & Technology (Missouri S&T) during the 2009 Fall semester (August 2009 to December 2009). This graduate student is running the SLS machine at Missouri S&T, upon guidance of Prof. Ming Leu (advisor and subcontract PI), and Prof. Greg Hilmas (both at Missouri S&T). The work includes designing of experiments, conducting the SLS-experiments, analyzing data and information, and reporting to advisor and to Dr. Mariano Velez, at Mo-Sci Corp., PI of NSF contract. The impact resulting from the Recovery Act Funds is to develop a new technique for fabricating 3-D scaffolds (duplicating bone parts) using bioactive glass 13-93 powder, <75 ìm particle size. The advantages of the proposed SLS-scaffolds include manufacturing contour-precision shapes, controlling porosity, and the possibility of making novel bone scaffolds with porosity gradients or structural gradients. (Total jobs reported: 1)
Project Status: More than 50% Completed
This award's data was last updated on Jun. 30, 2009. Help expand these official descriptions using the wiki below.
Funds from this award have been disbursed to subcontractors. Click here to see a list of subcontractors.