title: Biodistribution and biopersistence of ceria engineered nanomaterials: size dependence.
abstract: The aims were to determine the biodistribution, translocation, and persistence of nanoceria in the brain and selected peripheral organs. Nanoceria is being studied as an anti-oxidant therapeutic. Five, 15, 30, or 55 nm ceria was iv infused into rats which were terminated 1, 20, or 720 h later. Cerium was determined in blood, brain, liver, and spleen. Liver and spleen contained a large percentage of the dose, from which there was no significant clearance over 720 h, associated with adverse changes. Very little nanoceria entered brain parenchyma. The results suggest brain delivery of nanoceria will be a challenge.
  
  
  BACKGROUND
  This team of investigators revealed that nanoceria, which is being studied as an anti-oxidant, has very limited uptake by the brain regardless of the range of sizes studied, suggesting major challenges in the application of this novel approach in the central nervous system.
authors.affiliation: Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky, USA. ryokel@email.uky.edu
authors.forename: Robert A
authors.initials: RA
authors.lastname: Yokel
authors.forename: Michael T
authors.initials: MT
authors.lastname: Tseng
authors.forename: Mo
authors.initials: M
authors.lastname: Dan
authors.forename: Jason M
authors.initials: JM
authors.lastname: Unrine
authors.forename: Uschi M
authors.initials: UM
authors.lastname: Graham
authors.forename: Peng
authors.initials: P
authors.lastname: Wu
authors.forename: Eric A
authors.initials: EA
authors.lastname: Grulke
mesh_terms: D000818:Animals; D002563:Cerium / Q000493:pharmacokinetics*; D008099:Liver / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D012542:Scattering, Radiation; D013154:Spleen / Q000378:metabolism / Q000648:ultrastructure; D014018:Tissue Distribution
chemical_list: D002563:Cerium