title: Biological performance of a size-fractionated core-shell tantalum oxide nanoparticle x-ray contrast agent.
abstract: OBJECTIVE
  Metal-containing nanoparticles show great promise as x-ray contrast media and could enable reduced radiation dose, increased contrast, and the visualization of smaller anatomic features. In this study, we report progress toward these goals using a size-fractionated core-shell tantalum oxide nanoparticle contrast agent.
  
  
  METHODS
  A core-shell tantalum oxide nanoparticle contrast agent was synthesized and size fractionated for preclinical investigation of biodistribution, blood half-life, organ retention, and histopathology. Fractionated agent was injected at anticipated clinical dose and at 3 times the anticipated clinical dose to evaluate biological performance. Computed tomography (CT) imaging studies were also performed to evaluate short-term clearance kinetics and new imaging applications.
  
  
  RESULTS
  Improved control of 2-diethylphosphatoethylsilane-TaO nanoparticle size resulted in significantly reduced retention of injected tantalum. In vivo and in vitro CT imaging studies demonstrated short-term biodistribution differences in the kidney between small-molecule iodinated contrast media and fractionated 2-diethylphosphatoethylsilane-TaO, as well as preliminary data about new "Ta-only" imaging applications using multienergy CT image acquisition.
  
  
  CONCLUSIONS
  Size-fractionated core-shell tantalum oxide nanoparticles with a well-defined particle size distribution have several key features required of clinically viable vascular imaging compounds and may be used in developing multienergy CT imaging applications.
authors: GE Global Research Center, Niskayuna, NY 12309, USA. torres@ge.com
authors: Andrew S
authors: AS
authors: Torres
authors: Peter J
authors: PJ
authors: Bonitatibus
authors: Robert E
authors: RE
authors: Colborn
authors: Gregory D
authors: GD
authors: Goddard
authors: Paul F
authors: PF
authors: FitzGerald
authors: Brian D
authors: BD
authors: Lee
authors: Michael E
authors: ME
authors: Marino
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003287:Contrast Media; D004195:Disease Models, Animal; D005260:Female; D007668:Kidney / Q000528:radiation effects*; D008297:Male; D053758:Nanoparticles; D010087:Oxides; D051381:Rats; D011917:Rats, Inbred Lew; D013635:Tantalum; D014057:Tomography, X-Ray Computed; D001743:Urinary Bladder / Q000528:radiation effects*; D014965:X-Rays
chemical_list: D003287:Contrast Media; D010087:Oxides; D013635:Tantalum; C078151:tantalum oxide