title: In vivo biodistribution and accumulation of 89Zr in mice.
abstract: BACKGROUND
  The present investigation focuses on the chemical and biological fate of (89)Zr in mice. Electrophoreses of (89)Zr solvated or chelated in different conditions are here presented. The biological fate of mice injected with [(89)Zr]Zr-oxalate, [(89)Zr]Zr-chloride, [(89)Zr]Zr-phosphate, [(89)Zr]Zr-desferrioxamine and [(89)Zr]Zr-citrate is studied with the biodistribution, the clearances and positron emission tomography images. A special focus is also given regarding the quality of (89)Zr bone accumulation.
  
  
  METHODS
  Electrophoreses were carried out on chromatography paper and read by gamma counting. Then, the solutions were intravenously injected in mice, imaged at different time points and sacrificed. The bones, the epiphysis and the marrow substance were separated and evaluated with gamma counts.
  
  
  RESULTS
  The clearances of [(89)Zr]Zr-chloride and [(89)Zr]Zr-oxalate reached 20% of injected dose (ID) after 6 days whereas [(89)Zr]Zr-phosphate was only 5% of ID. [(89)Zr]Zr-citrate and [(89)Zr]Zr-DFO were noticeably excreted after the first day postinjection (p.i.). [(89)Zr]Zr-chloride and [(89)Zr]Zr-oxalate resulted in a respective bone uptake of ∼15% ID/g and∼20% ID/g at 8 h p.i. with minor losses after 6 days. [(89)Zr]Zr-citrate bone uptake was also observed, but [(89)Zr]Zr-phosphate was absorbed in high amounts in the liver and the spleen. The marrow cells were insignificantly radioactive in comparison to the calcified tissues.
  
  
  CONCLUSIONS
  Despite the complexity of Zr coordination, the electrophoretic analyses provided detailed evidences of Zr charges either as salts or as complexes. This study also shows that weakly chelated, (89)Zr is a bone seeker and has a strong affinity for phosphate.
authors: Department of Radiology, Radiochemistry Service, Memorial Sloan Kettering Cancer Center, Box 16, New York, NY 10065, USA. aboud@mskcc.org
authors: Diane S
authors: DS
authors: Abou
authors: Thomas
authors: T
authors: Ku
authors: Peter M
authors: PM
authors: Smith-Jones
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000000981:diagnostic imaging / Q000378:metabolism; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000378:metabolism; D002021:Buffers; D004586:Electrophoresis; D005260:Female; D007267:Injections; D008657:Metabolic Clearance Rate; D051379:Mice; D049268:Positron-Emission Tomography; D011868:Radioisotopes / Q000302:isolation & purification / Q000378:metabolism / Q000493:pharmacokinetics*; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D015040:Zirconium / Q000302:isolation & purification / Q000378:metabolism / Q000493:pharmacokinetics*
chemical_list: D002021:Buffers; D011868:Radioisotopes; D012996:Solutions; D012997:Solvents; D015040:Zirconium