Pb 203
51.9 h
γ 279, 401...

Chemical properties

Pb-203 is usually in divalent state.

Nuclear properties

Pb-203 decays by electron capture (100 % EC) to stable Tl-203, followed by the emission of one dominant γ-ray at 279.2 keV (80.94(6)%) and X-rays, notably Kα at ≈72 keV (58.8(3) %) and Kβ at ≈83 keV (16.3(3) %). These energies make Pb-203 suitable for SPECT (single photon emission computed tomography) imaging. The mean electron energy emitted per decay is 44 keV, the mean photon energy per decay is 314 keV.


Pb-203 is produced via deuteron irradiation of Tl-205 targets at ARRONAX (Nantes, France), followed by a radiochemical Pb/Tl separation via ion exchange chromatography.


Irradiation and radiochemical separation are performed at ARRONAX (Nantes, France). Activity will be shipped from there to the users in form of 1 M ammonium acetate solution.

Examples of use

  • Pb-203 has been used as radiotracer in toxicology studies to quantify uptake and release of lead compounds , ,
  • Different lead-specific chelators have been reported , ,
  • Pb-203 may serve as imaging surrogate in the Pb-203/Pb-212 theranostic pair where the latter acts in turn as Pb-212/Bi-212 in-vivo generator of the alpha-emitter Bi-212 ,

Purity grades available


No carrier added (n.c.a.)

Production routeTl-205(d,4n)Pb-203
DaughterDecays to stable Tl-203
Half-life51.92 hours
ProcessingIon exchange chromatography
Primary ContainerBorosilicate glass V-vial with silicon rubber screw cap
Product Graden.c.a.
Physical FormLiquid
Chemical Form1 M ammonium acetate
Radioactive Concentration (gamma spectrometry)n.a.
AppearanceClear colourless solution
Radionuclide identification (gamma spectrometry)279.2 keV (81%), 401.3 keV (3.35%),
Radionuclidic Purity (gamma spectrometry)>98%
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)n.a.
Additional information
Activity availablen.a.
Activity limit for UN2910 (excepted package) shipment3 GBq (solid form) or 300 MBq (liquid form)
Other information-



Point of supply

  • Nantes, France

Involved production facilities


Involved biomedical facilities

To find out in which biomedical facilities you can use this radionuclide, contact the helpdesk.