Sc 47
3.35 d
β- 0.4, 0.6
γ 159

Chemical properties

Sc-47 is a rare earth, usually in trivalent state. It can be radiolabelled with macrocyclic chelators, in particular DOTA.The ionic radius is 74.5 pm.

Nuclear properties

Sc-47 decays by beta-minus emission with a half-life of 3.3492(6) days to stable Ti-47. It emits a low energy beta spectrum with 162 keV average energy and 600 keV maximum energy. Emission of conversion and Auger electrons is negligible (<1%).

Moreover, Sc-47 emits gamma-rays at 159.4 keV (68.3%) suitable for SPECT-imaging.

The mean electron energy emitted per decay is 162 keV, the mean photon energy per decay is 109 keV .

Production

Sc-47 is produced indirectly by thermal neutron irradiation of enriched Ca-46 oxide or carbonate targets in the research reactors of the PRISMAP network: RHF at ILL, BR2 at SCK CEN and MARIA at NCBJ. The Ca-47 (T1/2=4.54 d) produced upon neutron capture decays to Sc-47 via beta-minus decay and serves as a generator, allowing several subsequent elutions of Sc-47 . With respect to other production pathways of Sc-47, this production scheme provides optimum radionuclidic purity .

Distribution

The radiochemical separations are performed at POLATOM (NCBJ, Otwock-Swierk, Poland). Activity will be shipped from there to the users in form of ScCl3 solution, ready for labelling of e.g. DOTA-compounds.

Examples of use

  • See for dosimetric calculations of Sc-47 in comparison to other beta-minus emitters.
  • Preclinicial bone scintigraphy with Sc-47 had been reported long ago .
  • The preclinical SPECT imaging capabilities of Sc-47 have been demonstrated .
  • The therapeutic efficacy of Sc-47-DOTA-folate has been compared preclinically with Lu-177-DOTA-folate and Y-90-DOTA-folate .
  • Different Sc-47 labelled PSMA-ligands have been tested preclinically .

Purity grades available

preclinical

No carrier added (n.c.a.)

Yes
ParameterSpecifications
Half-life3.35 d
DaughterStable Ti-47
Branching Ratio/Decay100% β-
ProductionCa-46(n,γ)Ca-47(β-)Sc-47
Purification2 steps column separation
Chemical FormIn 0.05 M HCl or 4.85 M NaCl /0.13 M HCl
Specific Activity1 GBq/mg
Radionuclidic Purity> 99.95% (< 0.005% Sc-46)
Radiochemical PurityLabelling up to 10-25 MBq/nmol DOTANOC (>96%) or ≈10 MBq/nmol DOTATATE (>95%)
Identification159.4 keV gamma line present
AppearanceClear and colourless solution
pH1-2
Activity availableUp to 500 MBq
Availabilityfew times per year (planning in advance), depends on reactor schedules
GradePreclinical grade, n.c.a.

Applications

  • β-therapy
  • SPECT

Point of supply

  • Otwock-Swierk, Poland

Involved production facilities

SCK CEN, Belgium
ILL, France
NCBJ, Poland