title: 99mTc-phytate as a diagnostic probe for assessing inflammatory reaction in malignant tumors.
abstract: OBJECTIVE
  Once administered intravenously, technetium-99m (99mTc)-labeled phytate binds to calcium in the serum and behaves as a nanoparticle. On the basis of the high permeability of the tumor vasculature, 99mTc-phytate is expected to leak and accumulate specifically in inflammatory cells. The aim of this study was to evaluate the potential of 99mTc-phytate in assessing the degree of inflammation in Ehrlich solid tumors in mice.
  
  
  METHODS
  99mTc-phytate was prepared by adding pertechnetate to a solution containing phytic acid and stannous chloride. The blood half-life of this particle following intravenous injection was determined using blood samples from healthy animals, whereas its size was measured by photon correlation spectroscopy. Scintigraphic imaging and biodistribution studies were carried out in tumor-bearing mice at 30 min and 2 h after injection.
  
  
  RESULTS
  The average size of the particles was in the range of 200 nm, suggesting that they are capable of passively passing through fenestrations in tumor vessels, which are 200-2000 nm in size. The blood half-life for 99mTc-phytate was found to be 2.1 min, a result that is in agreement with previous studies. Data from tumor-bearing mice showed high tumor uptake at 2 h after 99mTc-phytate administration. As a result, a high tumor-to-muscle ratio was achieved (T/M = 25.9 ± 7.54).
  
  
  CONCLUSIONS
  These findings indicate that 99mTc-sodium phytate has promising properties for identifying the type of tumor. This approach will have significant implications for characterizing tumor biology and treatment of malignant lesions.
authors.affiliation: aFaculty of Pharmacy bFaculty of Medicine, Universidade Federal de Minas Gerais, Av. Alfredo Balena, Minas Gerais, Brazil cDepartment of Radiation Oncology dStanford University School of Medicine, Stanford, California eDepartment of Radiology, Hospital of the University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA fDepartment of Nuclear Medicine, Santa Maria della Misericordia Hospital, Rovigo, Italy.
authors.forename: Renata S
authors.initials: RS
authors.lastname: Fernandes
authors.forename: Luciene G
authors.initials: LG
authors.lastname: Mota
authors.forename: Anusha
authors.initials: A
authors.lastname: Kalbasi
authors.forename: Mateen
authors.initials: M
authors.lastname: Moghbel
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Werner
authors.forename: Abass
authors.initials: A
authors.lastname: Alavi
authors.forename: Domenico
authors.initials: D
authors.lastname: Rubello
authors.forename: Valbert N
authors.initials: VN
authors.lastname: Cardoso
authors.forename: Andre Luis B
authors.initials: AL
authors.lastname: de Barros
mesh_terms: D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000150:complications / Q000000981:diagnostic imaging*; D007249:Inflammation / Q000150:complications / Q000000981:diagnostic imaging; D051379:Mice; D010316:Particle Size; D010833:Phytic Acid / Q000737:chemistry* / Q000493:pharmacokinetics; D011854:Radiochemistry; D011877:Radionuclide Imaging; D013667:Technetium / Q000737:chemistry*; D014018:Tissue Distribution
chemical_list: D013667:Technetium; D010833:Phytic Acid