SBIR Phase I: Robust Bench-Top Oxygen Imager for Tissue Graft Viability Assessment

This SBIR Phase I project will address a problem of poor oxygen delivery to the core of artificial tissues by providing reliable means of three-dimensional oxygen mapping in vitro and in vivo. The field of tissue engineering regenerative medicine combines the principles of the life sciences, cell biology, and engineering to create functional tissues and organs that can be used for replacing damaged tissues and organs. The public health benefit of replacing damaged tissues and organs is at par with curing cancer. Almost every part of the human body has been considered for replacement. Tissue engineering strives to solve arthritis, Type I diabetes, stroke, vascular diseases, liver and kidney damages, and many other medical problems by replacing or restoring damaged tissues or organs with artificial functional tissues. This project will address the problem of poor oxygen transport in artificial tissue grafts, which is one of the major causes of tissue failure, by developing an oxygen imaging instrument to generate three-dimensional in situ oxygen maps. This instrument will allow scientists to assess oxygen environment over the time of graft production and upon implantation and develop better artificial tissues. The oxygen imager uses cutting-edge radiofrequency and magnet technology and will help create high-tech jobs in the Midwest. The oxygen imager will be based on the innovative noninvasive electron paramagnetic resonance oxygen imaging (EPROI) technology. EPROI uses an injectable water-soluble, non-toxic contrast agent, trityl that has oxygen-dependent relaxation rates. EPROI provides absolute partial oxygen pressure (pO2) maps with high accuracy (~ 1 torr) within 1-10 minutes. The oxygen imager will be equipped with a 25 mT magnet and ~720 MHz electronics suitable for in vitro and small animal in vivo oxygen imaging. The instrument will have user-friendly software for image acquisition, image registration, data processing and analysis. This project will develop the magnet with the top loading of samples along with temperature and gas controlled bioreactor sample chamber for in vitro oxygen mapping of artificial tissues. The robustness and performance of the imager will be tested by acquiring oxygen maps of cell-seeded biomaterials. It is expected that the oxygen imager will become an essential tool in tissue engineering labs of academic institutions and biotech companies and will have a major impact on the successful development of regenerative medicine therapies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.