Sm 153
1.93 d
β- 0.7, 0.8...
γ 103, 70...

Chemical properties

Sm-153 is a radiolanthanide, usually in trivalent state. It can be radiolabelled with macrocyclic chelators, in particular DOTA. The ionic radius is 95.8 pm.

Nuclear properties

Sm-153 decays by β- decay with a half-life of 1.9285(2) days to stable Eu-153. It emits a low to medium energy β- spectrum with 225 keV average energy and 808 keV maximum energy. In addition to β- emission it shows ample emission of low energy conversion and Auger electrons , thus emitting in total about 2.34 electrons (with energies above 4 keV) per decay.

Moreover, Sm-153 emits γ-rays at 103 keV (29.14%) suitable for SPECT imaging.

The mean electron energy emitted per decay is 265 keV, the mean photon energy per decay is 62 keV .

Production

Sm-153 is produced by thermal neutron irradiation of enriched Sm-152 oxide targets in the BR2 reactor at SCK CEN. The produced carrier-added Sm-153 is then mass separated at the MEDICIS facility at CERN. Thus, Sm-153 with high specific activity is obtained .

Distribution

A final radiochemical separation is performed at SCK CEN (Mol, Belgium). Activity will be shipped from there to the users in form of SmCl3 solution, ready for labelling of e.g. DOTA-compounds.

Examples of use

  • c.a. Sm-153 with limited specific activity is mainly used for bone pain palliation, commercially available under the brand name Quadramet®.
  • The high-specific activity variant described here enables applications for receptor-targeted radionuclide therapy.
  • Sm-153 is also suited as source for Mößbauer spectroscopy , a highly sensitive technique to characterize the chemical state and chemical environment of samarium bound in solids or frozen ex vivo samples.

Purity grades available

preclinical

No carrier added (n.c.a.)

Available in n.c.a. form (but not in theoretical specific activity)
ParameterSpecifications
Production routeSm-152(n,γ)Sm-153
DaughterDecays to stable Eu-153: 100% β-
Half-life1.93 d
ProcessingOff-line mass separation (CERN-MEDICIS) + 3-step column separation
Primary Container2.5 mL borosilicate glass V-vial with silicon rubber screw cap
Product Graden.c.a. (but not in theoretical molar activity)
Physical FormLiquid or solid deposit
Chemical FormIn 0.05 M HCl (evaporation to dryness is also possible)
Radioactive Concentration (gamma spectrometry)> 50 MBq/ml
AppearanceClear colourless solution
Radionuclide identification (gamma spectrometry)70 keV, 97 keV and 103 keV gamma lines present
Radionuclidic Purity (gamma spectrometry)>99.99%
Chemical purity (ICP-OES)n.a.
Molar activity (ICP-OES)280 GBq/µmol Sm at time of mass separation (>11% of theoretical maximum)
Apparent Molar ActivityLabelling up to 50 MBq/nmol p-SCN-Bn-DOTA and DOTATATE
Microbiological qualityn.a.
Bacterial endotoxinn.a.
pH (pH strips)1-2
Additional information
Activity availableUp to 150 MBq on demand (availability CERN-MEDICIS + BR2 reactor cycle)
Activity limit for UN2910 (excepted package) shipment0.6 GBq in dry state or 60 MBq in liquid form
Other informationLabelling up to 50 MBq/nmol p-SCN-Bn-DOTA and DOTATATE

Applications

  • β-therapy
  • SPECT

Point of supply

  • Mol, Belgium

Involved production facilities

SCK CEN, Belgium
CERN, International