title: Histological study of the biodynamics of iron oxide nanoparticles with different diameters.
abstract: The biodynamics of ultrasmall and small superparamagnetic iron oxide (USPIO and SPIO, respectively) particles that were injected intraperitoneally into 36 C57BL/6 mice were investigated chronologically. Their distribution was studied histologically at six time points by measuring iron-positive areas (μm²) in organ sections stained with Prussian blue. The uptake of the differently sized particles was also compared by cultured murine macrophages (J774.1). Iron-positive areas in the liver were significantly larger in the mice injected with USPIO than those injected with SPIO at the first three time points (P < 0.05). The amount of USPIO in the lung parenchyma around the airway was larger than that of SPIO at four time points (P < 0.05); distribution to the lymph nodes was not significantly different. The amount of iron was significantly larger in SPIO- than USPIO-treated cultured cells (P < 0.05). In conclusion, it is suggested that intra peritoneally injected USPIO particles could be used more quickly than SPIO to make Kupffer images of the liver and that both agents could help get lymph node images of similar quality.
authors.affiliation: Department of Radiology, Shiga University of Medical Science, Otsu, Shiga. keikot@belle.shiga-med ac.jp
authors.forename: Keiko
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Norihisa
authors.initials: N
authors.lastname: Nitta
authors.forename: Akinaga
authors.initials: A
authors.lastname: Sonoda
authors.forename: Ayumi
authors.initials: A
authors.lastname: Nitta-Seko
authors.forename: Shinichi
authors.initials: S
authors.lastname: Ohta
authors.forename: Hideji
authors.initials: H
authors.lastname: Otani
authors.forename: Masashi
authors.initials: M
authors.lastname: Takahashi
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Murata
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Murase
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nohara
authors.forename: Kenichi
authors.initials: K
authors.lastname: Mukaisho
mesh_terms: D000818:Animals; D002460:Cell Line; D003287:Contrast Media / Q000737:chemistry; D005260:Female; D052203:Ferrosoferric Oxide / Q000737:chemistry / Q000493:pharmacokinetics*; D006651:Histocytochemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry / Q000648:ultrastructure*; D051379:Mice; D008810:Mice, Inbred C57BL; D010316:Particle Size; D013054:Spectrophotometry, Atomic; D014018:Tissue Distribution
chemical_list: D003287:Contrast Media; D058185:Magnetite Nanoparticles; D052203:Ferrosoferric Oxide