Article

Simultaneous production of high specific activity 64Cu and 61Co with 11.4 MeV protons on enriched 64Ni nuclei.

Department of Medical Physics, University of Wisconsin Medical School, Madison, WI 53706, USA.
Applied Radiation and Isotopes (impact factor: 1.17). 10/2007; 65(10):1115-20. DOI:10.1016/j.apradiso.2007.05.012 pp.1115-20
Source: PubMed

ABSTRACT The (64)Cu and (61)Co radionuclides were produced simultaneously by irradiation of enriched (64)Ni on a low energy proton-only cyclotron. Nickel targets were prepared by electrodeposition of enriched (64)Ni (>95%) on Au backing at thicknesses of 25-225 mg/cm(2) with efficiencies >99%. Irradiations up to 30 microA for 8h were performed with 11.4 MeV protons using a water-cooled target mounting. Radiochemical separation of (64)Cu and (61)Co from (64)Ni was performed by chromatography of the chlorocomplexes in a single step using an anion exchange resin column with a yield >95%. Using this method, the Ni target material was recovered and re-plated for subsequent production runs with an overall efficiency >96%. The excitation function for the (64)Ni(p,n)(64)Cu reaction was measured and compared with published values. Experimental thick target saturation yields of 159 mCi/microA for (64)Cu and 715 microCi/microA for (61)Co were achieved. Typical specific activities of (64)Cu were found to be 18.8+/-3.3 Ci/micromol.

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    Michael R Benoit, Dirk Mayer, Yoram Barak, Ian Y Chen, Wei Hu, Zhen Cheng, Shan X Wang, Daniel M Spielman, Sanjiv S Gambhir, A Matin
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    Clinical Cancer Research 09/2009; 15(16):5170-7. · 7.74 Impact Factor
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Keywords

30 microA
 
715 microCi/microA
 
anion exchange resin column
 
Au
 
efficiencies >99%
 
electrodeposition
 
Experimental thick target saturation yields
 
low energy proton-only cyclotron
 
Ni target material
 
Nickel targets
 
re-plated
 
single step