Chemical properties
Cu-64 is a versatile radionuclide, used in nuclear medicine for both diagnostic imaging and targeted radiotherapy, functioning as a true theranostic agent. In solution copper is usually in divalent state and can be radiolabelled with macrocyclic chelators. To bypass the in-vivo transchelation risk by endogenous proteins cyclic chelators (like DOTA, which undergoes slow Cu(II) dissociation in vivo) are replaced by other, highly robust macrocyclic, specific copper chelators such as Me-COSar, DiAmSar or CB-TE2A, CB-DO2A REF,REF,REF.
Nuclear properties
Cu-64 decays with a half-life of 12.70 h by β+ decay (17.6%) or electron capture (43.9%) to stable Ni-64 and by β- emission (38.5%) to stable Zn-64 respectively. The emitted positrons have 278 keV average energy and 653 keV maximum energy and the emitted low energy β- spectrum has 191 keV average energy and 579 keV maximum energy.
In addition to β- emission it also emits low energy Auger electrons REF, thus emitting in total about 0.79 electrons or positrons (with energies above 6 keV) per decay.
Cu-64 emits only one weak γ-ray at 1345.8 keV (0.48%).
The total electron energy emitted per decay is 124 keV, the total photon energy per decay is 187 keV REF.
Production
Cu-64 can be produced by a variety of facilities by proton irradiation of enriched Ni-64 targets at CCR at IFIN-HH (TR19), Hevesy Laboratory at DTU, C30 cyclotron at NCBJ and TR-FLEX cyclotron at HZDR, or by deuteron irradiation of enriched Ni-64 targets at ARRONAX.
Distribution
The radiochemical separation is performed at the same laboratory where the irradiation took place. Activity will be shipped from there to the users in solution or in the form of a dried deposit.
Examples of use
|
| Parameter | Specifications |
|---|---|
| Production route (cyclotron) | Ni-64(p,n)Cu-64 [or Ni-64(d,2n)Cu-64 at ARRONAX] |
| Decay | Decays to stable Ni-64 and stable Zn-64: 17.6% β+, 43.9% EC, 38.5% β- |
| Half-life | 12.7 h |
| Processing | One step ion exchange chromatography |
| Primary Container | 2.5 mL borosilicate glass V-vial with silicone rubber screw cap |
| Product Grade | n.c.a. |
| Physical Form | |
| Chemical form | CuCl2 in dry form or solution |
| Radioactive Concentration (gamma spectrometry) | n.a. |
| Appearance | Invisible deposit at bottom of glass vial / Transparent liquid |
| Radionuclide Identification (gamma spectrometry) | 1346 keV gamma line and 511 keV annihilation gamma line present |
| Radionuclidic purity (gamma spectrometry) | >99.9% at calibration time (Co-56, Co-57, Co-58 each below 0.01%) |
| Chemical purity (ICP-OES) | Ni, Zn, Co and Fe each <1 µg per GBq Cu-64 |
| Molar activity (ICP-OES) | >500 GBq/µmol at calibration time (>5% of theoretical maximum) |
| Apparent Molar Activity | >100 GBq/µmol (DOTA labelling) at calibration time |
| Microbiological quality | Sterile |
| Bacterial endotoxin | <175/V IU/ml (V being the maximum volume to be used for the preparation of a single patient dose) |
| pH (pH strips) | n.a. |
| Additional information | |
| Activity available | |
| Activity limit for UN2910 (excepted package) shipment | 1 GBq in dry state or 0.1 GBq in liquid form |
| Other information | Product is normally shipped in dry state, in “empty vials” but ready for reconstitution with what buffer the user prefers, and then ready for labelling of e.g. DOTA-compounds. Upon request, product can be shipped in 0.05 M HCl (1-2 ml) or Ammonium Acetate buffer (1 M, 1-2 ml). Bioburden and endotoxin burden can be analysed post release, upon request. Product is also available as Cu-64-ATSM from ARRONAX. |
