Determining the Distribution of Nano-particles Magnetic Iron Oxide in Mice by ~(59)Fe Tracer

To observe the distribution of nano-particles iron oxide as a magnetic resonance contrast agent in mice, magnetic iron oxide(SUMR) is coated with macromolecular labeled by 59 Fe and the distribution in blood, heart, lung, liver, spleen, kidneys, bone, muscle and urine of mice are determined. Main uptake of 59 Fe-SUMR is in liver and spleen. The maximum is 95.07±8.27 %ID/g and 53.93±5.94 %ID/g at 30 min and 24 h after injection of 59 Fe-SUMR, respectively. 59 Fe-SUMR in blood is initially rapid decreased, then gradually increased and the peak value is appeared at 15 days after injection. The normal level of 59 Fe-SUMR is achieved at 60 days after injection. SUMR is promised to well be used as a magnetic resonance contrast agent for liver and spleen diseases.