Critical Enhancements of MRI Contrast and Hyperthermic Effects by Dopant-Controlled Magnetic Nanoparticles


  • We thank Prof. H. Ju and J. C. Moon for magnetic property measurements, and Dr. Y.-w. Jun and Dr. J.-w. Seo for helpful discussions. We thank J.-G Kim and Y.-J. Kim for TEM analyses (JEM-ARM1300S). This work was supported in part by the National Research Laboratory (R0A-2006-000-10255-0), 2nd stage BK21, AFOSR–AOARD (FA4869-08-1-4016), and the NCI Center for Cancer Nanotechnology Excellence (CCNE).


Doped up: The incorporation of Zn2+ dopants in tetrahedral sites leads to the successful magnetism tuning of spinel metal ferrite nanoparticles (see picture). (Zn0.4Mn0.6)Fe2O4 nanoparticles exhibit the highest magnetization value among the metal ferrite nanoparticles. Such high magnetism results in the largest MRI contrast effects (r2=860 mm−1 s−1) reported to date and also huge hyperthermic effects.

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