Properties:
51Cr is a gamma emitter (10% at 320 keV) decaying through electron capture (752 KeV, 90% and 432 keV, 10%) with a half-life of 27.7 d. TVT is 9.5 cm for concrete and 0.6 cm for lead.
Manufacturing:
51Cr is usually obtained in reactors by neutron irradiation of 50Cr following the scheme [50Cr(n,γ)51Cr].
Source and availability:
Several reactors around the world are able to produce 51Cr. As the need is very small, there is no issue of availability. The product is in the catalogue of POLATOM in the form of chloride, chromate, or EDTA complex.
Derivatives:
51Cr is involved in non-imaging procedures for labeling of red blood cells, quantifying gastrointestinal protein loss and for the determination of glomerular filtration rate in the assessment of kidney function. 51Cr is mainly to be found in the product marketed by Amersham 51Cr-Edetate. 51Cr Sodium chromate (provide by e.g., Perkin Elmer, Bracco) is used for cell labeling in ex vivo tests.
Price:
EUR 100-300 (US$ 130–390) per mCi depending on the amount and the quality.
Issues:
The radionuclide and the associated tracer can be replaced by more readily available products with shorter half-lives.
Comments:
Due to the long half-life of this radionuclide, no research program is developed around it for radiopharmaceuticals and its use will be limited to the presently available products and will definitely fade over the next years.