Henry R. Chan1,2, Pratip Bhattacharya1, Ashraf Imam1, Anna Freundlich1, Thao Tran2, William H. Perman3, Alexander P. Lin1, Kent Harris1, Eduard Y. Chekmenev1, Marylou Ingram1, Brian D. Ross1
1Enhanced Magnetic Resonance Laboratory, Huntington Medical Research Institutes, Pasadena, CA, USA; 2Rudi Schulte Research Institutes, Santa Barbara, CA, USA; 3Department of Radiology, St. Louis University, St. Louis, MO, USA
Hyperpolarized 13C-enriched compounds can provide enough signal for magnetic resonance spectroscopy to potentially trace the metabolic processes of living cells, in situ. Preparatory to any clinical study, the safety profile of candidate tracer reagents and reaction catalysts must be characterized. We report that the rhodium norbordiene catalyst, critical to the PASADENA method of hyperpolarization, produces no clinical signs of disease in rats despite inhibiting growth in liver cell cultures. Intravenous succinate was also well tolerated up to a 300 mM (151.7 mg/kg) dose, well above the usual 10-30 mM imaging dose.