title: Dynamic nuclear polarization system output volume reduction using inert fluids.
abstract: OBJECTIVE
  To present a method for significantly increasing the concentration of a hyperpolarized compound produced by a commercial dynamic nuclear polarization (DNP) polarizer, enabling the polarization process to be more suitable for preclinical applications.
  
  
  METHODS
  Using a HyperSense DNP polarizer, we investigated the combined use of perfluorocarbon and water to warm and dissolve the hyperpolarized material from the polarization temperature of 1.4K to produce material at temperatures suitable for injection.
  
  
  RESULTS
  By replacing 75% of the water in the dissolution volume with a chemically and biologically inert liquid that is immiscible with water, the injection volume can be reduced 4-fold. Rapid separation of the water and perfluorocarbon mixture enables the aqueous layer containing polarized material to be easily and rapidly collected.
  
  
  CONCLUSIONS
  The approach provides a significantly increased concentration of compound in a volume for injection that is more appropriate for small animal studies. This is demonstrated for (13) C-labeled pyruvic acid and (13) C-labeled succinate, but may be applied to the majority of nuclei and compounds hyperpolarized by the DNP method.
authors: Department of Biomedical Engineering, University of Wisconsin, Madison, WI, USA. etpeterson@wisc.edu
authors: Eric T
authors: ET
authors: Peterson
authors: Jeremy W
authors: JW
authors: Gordon
authors: Matthew G
authors: MG
authors: Erickson
authors: Sean B
authors: SB
authors: Fain
authors: Ian J
authors: IJ
authors: Rowland
mesh_terms: D000818:Animals; D002247:Carbon Isotopes / Q000494:pharmacology*; D003952:Diagnostic Imaging / Q000379:methods*; D004867:Equipment Design; D005466:Fluorocarbons / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008422:Materials Testing; D051379:Mice; D008813:Mice, Inbred ICR; D008970:Molecular Weight; D019047:Phantoms, Imaging; D011773:Pyruvates / Q000737:chemistry; D019289:Pyruvic Acid / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D019802:Succinic Acid / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D005466:Fluorocarbons; D011773:Pyruvates; D014867:Water; D019289:Pyruvic Acid; D019802:Succinic Acid