Chemical properties
Manganese is a transition metal which belongs to Group 7 of the periodic table, which can exhibit multiple oxidation states ranging from +2 to +7, with +2, +4, and +7 being the most common in solution. It can be radiolabelled with macrocyclic chelators. DOTA is being used, and others are proposed REF.
Nuclear properties
Mn-52 decays with a half-life of 5.59 days by β+ decay (29.4(4)%) or electron capture (70.6%) to stable Cr-52. The emitted positrons have 242 keV average energy and 575 keV maximum energy.
Mn-52 emits a nearly prompt (41 ps level half-life) cascade of three hard γ-rays: 1434.1 keV (100%), 935.5 keV (94.5%) and 744.2 keV (90%) REF.
Hence, Mn-52 is a long-lived PET isotope with short positron range (similar to F-18) and good intrinsic resolution, but potential cross-talk from prompt γ-rays emission and significant γ dose rate.
The total electron energy emitted per decay is 74 keV, the total photon energy per decay is 3446 keV REF.
Production
Mn-52 is produced by proton irradiation of natural Cr targets 52Cr(p,n)⁵²Mn at Hevesy Laboratory at DTU and at CCR, IFIN-HH.
Distribution
The radiochemical separation is performed at Hevesy Laboratory (DTU, Risø, Denmark) and Radiopharmaceutical Research Centre (IFIN-HH, Magurele, Romania). Activity will be shipped from there to the users in solution or in the form of a dried deposit respectively.
Examples of use
| Parameter | Specifications |
|---|---|
| Production route | Cr-52(p,n)Mn-52 |
| Daughter | Decays to stable Cr-52: 29.4% β+, 70.6% EC |
| Half-life | 5.59 d |
| Processing | Multi-step extraction chromatography |
| Primary Container | 2.5 mL borosilicate glass V-vial with silicon rubber screw cap |
| Product Grade | n.c.a. |
| Physical Form | Liquid or dried deposit |
| Chemical Form | Mn2+ ion in 0.1 M HCl solution (1-2 ml) |
| Radioactive Concentration (gamma spectrometry) | n.a. |
| Appearance | Clear colourless solution or invisible dried deposit |
| Radionuclide identification (gamma spectrometry) | 744 keV, 936 keV and 1434 keV gamma lines and 511 keV annihilation gammas present |
| Radionuclidic Purity (gamma spectrometry) | >99% |
| Chemical purity (ICP-OES) | Metal impurities determined by ICP-OES for each batch. Typical 120 nmol Cr, 180 nmol Al, and 240 nmol Ca per batch (subject to revision) |
| Molar activity (ICP-OES) | > 200 GBq/µmol Mn at end of chemistry (>30% of theoretical maximum) |
| Apparent Molar Activity | n.a. |
| Microbiological quality | Bioburden and endotoxin burden can be analysed post release, upon request |
| Bacterial endotoxin | Bioburden and endotoxin burden can be analysed post release, upon request |
| pH (pH strips) | Depends on chemical form |
| Additional information | |
| Activity available | Up to 0.4 GBq, upon request |
| Activity limit for UN2910 (excepted package) shipment | 0.3 GBq in dry state or 30 MBq in liquid form |
| Other information |
