There was no statistically significant difference in the biodistribution of D-and DM-USPIO in tissues from the spleen and kidney. The values determined by Prussian blue staining in tissues of the spleen were 40,088 ± 10,480 vs 43,607 ± 9456 for D-and DM-USPIO, respectively, and submit your manuscript | www.dovepress.com Dovepress Dovepress were 1711 ± 1508 vs 758 ± 583, respectively, in kidney tissues. In the liver and lung, these values tended to be higher in DM-than D-USPIO-treated rabbits (18,118 ± 5027 vs 14,421 ± 5920 in the liver, and 1261 ± 1363 vs 169 ± 245 in the lung). There was no significant iron accumulation in cardiac tissues. In the controls, only the spleen (the ironstoring organ) showed significant iron deposits. In both D-and DM-USPIO-treated rabbits these levels were increased.