Dual use of nitroxyl radicals as a polarizing agent in hyperpolarization 13C-MRS and as a redox probe in EPR spectroscopy to study acute kidney injury

Motivation: Trityl radicals are the main polarizing agents used for hyperpolarization. However parallel monitoring of metabolic and redox conditions is an unmet need. Goal(s): To use nitroxides as a polarizing agent and as a redox probe simultaneously for the same sample. Approach: Four nitroxyl probes were tested. HyperSense DNP polarizer was used for 13C-pyruvate hyperpolarization.13C-MRS and EPR measurements were performed using same samples. Results: CmP showed the highest hyperpolarization signal. A significant reduction in 13C lactate production and EPR decay rates of CmP during disease progression were confirmed. Impact: We described successful application of nitroxyl radicals for simultaneous assessment of energy metabolism and redox status.