Tb-152 is a radiolanthanide, most often in trivalent state and chemically very similar to lutetium. The ionic radius of Tb3+ is 92 pm, i.e. just 7% larger than Lu3+, which explains that macrocyclic chelators suitable for Lu-177 can be directly employed for Tb-152 too, in particular DOTA, but also others .
Tb-152 decays by β+ decay (20.3%) or electron capture (79.7%) with a half-life of 17.5(1) hours to Gd-152. The mean positron energy is 1140(130) keV.
Tb-152 emits γ- and X-rays, notably a strong line of 63.5 % at 344.3 keV and about 52% at 43 (+/-1) keV). This makes Tb-152 a suitable isotope for PET imaging and possibly useful for 3-photon imaging.
Tb-152 emits few conversion and Auger electrons.
Tb-152 is produced by high energy proton induced spallation of tantalum targets at the production facility MEDICIS at CERN. An off-line mass separation is performed at MEDICIS at CERN. The mass-separated ions are implanted into a solid matrix, e.g. a Zn or NaCl layer on a noble metal backing. The implanted layer can be dissolved and used for an additional radiochemical separation to obtain optimum radionuclidic purity by removing the pseudo-isobar Ce-136 that is mass-separated as oxide ion on mass 152.
Tb-152 is produced by spallation reaction in thick tantalum targets with protons of high energy . The radionuclides are released from the target by distillation and separated as implanted ions into zinc-coated gold foils . The isotope implanted collections undergo then a dissolution and separation step.
Tb-152 implanted into a solid matrix will be shipped from MEDICIS (CERN, Geneva, Switzerland).
Examples of use
|Daughter||Decays to quasistable Gd-152: 20.3% β+, 79.7% EC|
|Processing||Off-line mass separation + 2-step column separation|
|Physical Form||Liquid or solid|
|Chemical Form||In 0.05 M HCl|
|Radioactive Concentration (gamma spectrometry)||n.a.|
|Radionuclide identification (gamma spectrometry)||344 keV and 586 keV gamma lines and 511 keV annihilation gamma rays present|
|Radionuclidic Purity (gamma spectrometry)||t.b.d.|
|Chemical purity (ICP-OES)||n.a.|
|Molar activity (ICP-OES)||n.a.|
|Apparent Molar Activity||n.a.|
|pH (pH strips)||t.b.d.|
|Activity available||50 MBq few times per year (planning in advance)|
|Activity limit for UN2910 (excepted package) shipment||20 MBq in dry state or 2 MBq in liquid form|
|Other information||Implanted in Al, Zn or NaCl layer on Au foil|