Bashar Issa1, Ihab M. Obaidat1, Shahnaz Qadri2, Basil al-Ramadi3, Yousef Haik2,4
1Physics, UAE University, Al-Ain, Abu Dhabi, United Arab Emirates; 2Mechanical Eng., UAE University, Al-Ain, Abu Dhabi, United Arab Emirates; 3Medicine, UAE University, Al-Ain, Abu Dhabi, United Arab Emirates; 4Center of Research Excellence in Nanobiosciences, Univ. of North Carolina-Greensboro, United States
We studied the of 1/T1 and 1/T2 behaviour and effect of PEG coating for a new class of magnetic nanoparticles (MNPs) Mn0.5Zn0.5GdxFe(2-x)O4 with Gd concentration x = 0.02. MNPs were dispersed in gel with a range of concentrations (in mM of Fe per kg) from 0.0 to 0.3. At 1.5 T, T1 and T2 were measured at temperatures 26 oC. The measured 1/T1 and 1/T2 show linear dependence on concentrations. Variation of R1,2 with concentration is larger for the uncoated than for the coated particles due to smaller distance separating the protons from MNPs. These nanoparticles have already been used as hyperthermia agents and we are investigating the extension of their use as MRI contrast agents.