Ryan Chamberlain1, Michael Etheridge2, Djaudat Idiyatullin1, Curt Corum1, John Bischof2, Michael Garwood1
1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States; 2Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, United States
Iron oxide magnetic nanoparticles (MNPs) are widely used in MRI as a T2- and T2*-shortening contrast agent. Quantifying high concentrations of MNPs is crucial in magnetic fluid hyperthermia for cancer therapy. Efforts to quantify MNP concentration have relied on T2* mapping; however, signal loss is a severe obstacle to quantifying high concentrations of MNPs based on traditional MRI methods. Here we use the SWIFT pulse sequence to accomplish T1 measurement of solutions with very high iron concentration and show how the measured T1 value may be used in place of T2* to quantify high concentrations of MNPs.