The nano-magnetic ferrofluid was prepared by chemical coprecipitation and its acute toxicology was investigated. The effective diameter (Eff. Diam. ) of the magnetic particles was about 19.9 nm, and the concentration of the ferrofluid was 17. 54 mg/ml. The acute toxic reaction and the main viscera pathological morphology of mice were evaluated after oral, intravenous and intraperitoneal administration of the nano-magnetic ferrofluid of different doses respectively. Half lethal dose (LD50) > 2104. 8 mg/kg,maximum non-effect dose (ED0) = 320. 10mg/kg with oral; LDs,> 438. 50 mg/kg, EDo = 160. 05 mg/kg with intravenous route; and LDso >1578. 6 mg/kg, ED0 = 320. 10 mg/kg with intraperitoneal administration. Degeneration and necrosis of viscera were not found. So the nano-magnetic ferrofluid, of which toxicity is very low, may be used as a drug carrier.
Ferrosoferric Oxide/chemical synthesis ; Ferrosoferric Oxide/*toxicity ; Magnetics ; Nanostructures/*toxicity

A magnetic metal organic framework (MMOF) was synthesized and used to separate Sr2+ in aqueous solution. The shape and structure of prepared Fe3O4@UiO-66-NH2 were characterized, and the absorbed concentration of strontium was determined through inductively coupled plasma mass spectrometry. The results indicated that Fe3O4 and UiO-66-NH2 combined through chemical bonding. The experimental adsorption results for separation of Sr2+ in aqueous solution indicated that the adsorption of Sr2+ to Fe3O4@UiO-66-NH2 increased drastically from pH 11 to pH 13. The adsorption isotherm model indicated that the adsorption of Sr2+ conformed to the Freundlich isotherm model (R2 = 0.9919). The MMOF thus inherited the superior qualities of magnetic composites and metal organic frameworks, and can easily be separated under an external magnetic field. This MMOF thus has potential applications as a magnetic adsorbent for low level radionuclide 90Sr.
Adsorption ; Ferrosoferric Oxide ; chemistry ; Hydrogen-Ion Concentration ; Metal-Organic Frameworks ; chemical synthesis ; chemistry ; Models, Theoretical ; Nanoparticles ; chemistry ; Strontium ; analysis ; Surface Properties ; Water Pollutants, Radioactive ; analysis ; Water Purification ; methods

OBJECTIVE: We wanted to compare the human neural stem cell (hNSC) labeling efficacy of different superparamagnetic iron oxide nanoparticles (SPIONs), namely, ferumoxides, monocrystalline iron oxide (MION), cross-linked iron oxide (CLIO)-NH2 and tat-CLIO. MATERIALS AND METHODS: The hNSCs (5x105 HB1F3 cells/ml) were incubated for 24 hr in cell culture media that contained 25 microgram/ml of ferumoxides, MION or CLIO-NH2, and with or without poly-L-lysine (PLL) and tat-CLIO. The cellular iron uptake was analyzed qualitatively with using a light microscope and this was quantified via atomic absorption spectrophotometry. The visibility of the labeled cells was assessed with MR imaging. RESULTS: The incorporation of SPIONs into the hNSCs did not affect the cellular proliferations and viabilities. The hNSCs labeled with tat-CLIO showed the longest retention, up to 72 hr, and they contained 2.15+/-0.3 pg iron/cell, which are 59 fold, 430 fold and six fold more incorporated iron than that of the hNSCs labeled with ferumoxides, MION or CLIO-NH2, respectively. However, when PLL was added, the incorporation of ferumoxides, MION or CLIO-NH2 into the hNSCs was comparable to that of tat-CLIO. CONCLUSION: For MR imaging, hNSCs can be efficiently labeled with tat-CLIO alone or with a combination of ferumoxides, MION, CLIO-NH2 and the transfection agent PLL.
Cells, Cultured ; Contrast Media/chemical synthesis/pharmacokinetics ; Cross-Linking Reagents/chemistry ; Ferric Compounds/chemistry/*pharmacokinetics ; Ferrosoferric Oxide/chemical synthesis/pharmacokinetics ; Gene Products, tat/chemistry ; Humans ; Iron/*pharmacokinetics ; Magnetic Resonance Imaging/methods ; Nanoparticles ; Neural Tube ; Oxides/*pharmacokinetics ; Phantoms, Imaging ; Polylysine/pharmacokinetics ; Spectrophotometry, Atomic ; Staining and Labeling/*methods ; Stem Cells/cytology/*drug effects/metabolism ; Time Factors ; Transfection

OBJECTIVETo synthesize Gal-BSA-SPIO as the magnetic resonance imaging (MRI) contrast agent targeting asialoglycoprotein (ASG) receptors in the liver and observe its role in MRI detection of hepatocellular carcinomas (HCCs).

METHODSGal-BSA was synthesized by means of reductive amination and mixed with SPIO in ice bath to prepare Gal-BSA-SPIO complex. Twenty rabbits bearing VX2 liver tumor underwent MRI enhanced by SPIO (n=10) and Gal-BSA-SPIO (n=10), and the T2 values of the liver and tumor before and after the contrast imaging were measured. Fresh human normal hepatic tissues (n=3), cirrhotic tissues (n=4) and HCC tissues (n=6) were obtained and incubated with Gal-BSA-SPIO followed by Perl's Prussian blue staining to observe the distribution of ASG receptors.

RESULTSThe size of the Gal-BSA-SPIO particles was 34.4 nm. The 20 rabbits bearing VX2 tumor, with tumor size ranging from 3 mm to 12 mm, showed isointense signal in the liver and hypointense signal in the tumor on T1WI, and isointense signal in the liver and slightly hyperintense signal in the tumor on GRE T2*WI. The signal intensity of the liver decreased slightly or moderately after administration of SPIO in the rabbits, and administration Gal-BSA-SPIO resulted in obvious reduction in the signal intensity of the liver. The signal intensities of the tumors did not exhibit obvious changes after the administration of SPIO or Gal-BSA-SPIO. Histological examination revealed numerous blue iron deposits in the Kupffer cells in SPIO group and in the hepatocytes in Gal-BSA-SPIO group, but not in the tumors in either of the groups. The human liver specimens incubated with Gal-BSA-SPIO contained numerous blue iron deposits in the hepatocyte cytoplasm and cell membrane in normal liver tissue, but the deposits were reduced in the cirrhotic tissue and almost absent in the HCC tissue.

CONCLUSIONGal-BSA-SPIO can specifically bind to ASG receptors on hepatocyte membrane to improve the tumor-liver contrast-to-noise ratio.

Animals ; Asialoglycoprotein Receptor ; chemistry ; metabolism ; Contrast Media ; chemical synthesis ; Dextrans ; Female ; Ferric Compounds ; chemistry ; Ferrosoferric Oxide ; chemistry ; Galactose ; chemistry ; Humans ; Image Enhancement ; methods ; Image Processing, Computer-Assisted ; Liver ; metabolism ; Liver Neoplasms ; diagnosis ; metabolism ; pathology ; Liver Neoplasms, Experimental ; pathology ; Magnetic Resonance Imaging ; methods ; Magnetite Nanoparticles ; Male ; Rabbits ; Serum Albumin, Bovine ; chemistry