This Small Business Innovation Research (SBIR) Phase-I project proposes to fabricate a new, innovative instrument for efficient, noninvasive, in vivo imaging of tumor oxygenation and pH by using Overhauser Enhanced Magnetic Resonance Imaging (OMRI). Such instruments are not commercially available. Tumor hypoxia and acidosis are hallmarks of cancer that are critical for understanding complex cancer biology, and to assess anti-cancer chemotherapies in longitudinal studies of mouse models. Yet non-invasively quantifying tumor hypoxia and acidosis during longitudinal studies remains challenging. This innovation includes cycling of the magnetic field strength between low fields for EPR irradiation (< 200 Gauss) to high field for MRI data acquisition (4700 Gauss). The unique field-cycling electronics and custom magnet design will enable the fast switching of the magnetic field strength in less than 10 msec. With this new system the technology would enable the mapping of oxygen partial pressure and pH in tumors and other biological tissues. In addition, it represents for researchers a new tool to evaluate novel contrast agent designs and/or modify existing ones.
The broader impact/commercial potential of this project will be to raise the technical and performance ceiling of magnetic field cycling to new heights. This capability will encourage and support researchers to develop new contrast agents for hyperpolarization that will greatly improve sensitivity. The instrumentation will allow quantification of pO2 and pH, as well as redox potential during pre-clinical in vivo investigations pertinent to understanding carcinogenesis and/or development of improved cancer therapies. Furthermore, our resistive and electrically powered solenoid magnet will change the perception that such magnets cannot be used for MRI. This innovation will open the door to a new and unique approach to generate stable magnetic fields using electrically resistive solenoids. Researchers in cancer biology and cancer therapeutics will be very interested in potential applications of this new methodology. In addition, researchers measuring relaxation times at low magnetic fields will be potential customers. Presently there are no companies in the United States providing such systems
