Tb 152
17.5 h
ε
β+ 3.0, 2.6, 2.0...
γ 344, 271, 586...

Chemical properties

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 .

Nuclear properties

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.

Production

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.

Distribution

Tb-152 implanted into a solid matrix will be shipped from MEDICIS (CERN, Geneva, Switzerland).

Examples of use

  • Tb-152 is part of the terbium radionuclide quadruplet , and can thus offer interesting imaging capacity, notably for PET and possibly also 3-photon imaging. Its extended half-life allows to perform dosimetric and imaging studies over several days. It was in particular used with antibody fragments .
  • A first in human PET/CT imaging was performed with Tb-152-DOTATOC over 24 hours , as well as with Tb-152-PSMA617 .

Purity grades available

research

No carrier added (n.c.a.)

Yes
ParameterSpecifications
Production routeTa(p,spallation)
DaughterDecays to quasistable Gd-152: 20.3% β+, 79.7% EC
Half-life17.5 h
ProcessingOff-line mass separation + 2-step column separation
Primary Container
Product Graden.c.a.
Physical FormLiquid or solid
Chemical FormIn 0.05 M HCl
Radioactive Concentration (gamma spectrometry)n.a.
Appearancen.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 Activityn.a.
Microbiological qualityn.a.
Bacterial endotoxinn.a.
pH (pH strips)t.b.d.
Additional information
Activity available50 MBq few times per year (planning in advance)
Activity limit for UN2910 (excepted package) shipment20 MBq in dry state or 2 MBq in liquid form
Other informationImplanted in Al, Zn or NaCl layer on Au foil

Applications

  • PET

Point of supply

  • Geneva, Switzerland

Involved production facilities

CERN, International