Ag-111 decays by beta-minus emission with a half-life of 7.45 days to stable Cd-111. It emits a medium energy beta spectrum with 350 keV average energy and 1037 keV maximum energy, similar to e.g. Re-186.
Moreover Ag-111 emits gamma-rays at 342.1 keV (6.7%) making it SPECT-imageable with high-energy collimators.
Ag-111 is produced indirectly by thermal neutron irradiation of enriched Pd-110 targets in the research reactors of the PRISMAP network: RHF at ILL, BR2 at SCK CEN or MARIA at NCBJ. The short-lived Pd-111 produced upon neutron capture on Pd-110 decays quickly (T1/2=23.4 min) to Ag-111 via beta-minus decay. A radiochemical Ag/Pd separation via ion exchange chromatography leads to n.c.a. Ag-111.
Radiochemical separations are performed at the PRISMAP facility Hevesy Laboratory (DTU, Risø, Denmark). Activity will be shipped from there to the users in form of Ag+ solution.
Examples of use
|Branching Ratio/Decay||100% β-|
|Purification||Ion exchange chromatography|
|Chemical Form||Ag+ ion in water or weak (<0.1 M) HCl solution (1-2 ml)|
|Chemical Purity||Metal impurities determined by ICP-OES for each batch|
|Identification||342.1 keV and 245.4 keV gamma lines present|
|Appearance||Clear colourless solution|
|Activity available||~1 GBq (more to be discussed)|
|Availability||Few times per year (planning in advance)|
|Grade||Preclinical grade, n.c.a.|
|Other information||Bioburden and endotoxin burden can be analysed post release, upon request.|