Terbium-161

Terbium-161 NCA

Terbium-161 is redefining targeted radiotherapy. With its unique emission of both beta particles and conversion/Auger electrons, Tb-161 delivers potent, localized radiation, ideal for treating small tumors and micrometastases with high precision and minimal damage to surrounding healthy tissue.

Why Terbium-161?

Terbium-161 is a next-generation therapeutic radionuclide that combines the proven benefits of lutetium-177 with an added advantage:

  • High-energy Auger electrons for enhanced tumor cell kill
  • Comparable chemistry to Lu-177 for easy integration into existing radiopharmaceutical platforms
  • Ideal for small tumors and micrometastases
  • NCA Grade: No Carrier Added for high specific activity and purity
  • GMP Production: Pharmaceutical-grade reliability, ready for clinical use
Clinical Potential
  • Designed for targeted radionuclide therapy (TRT)
  • Especially effective for neuroendocrine tumors, prostate cancer, and beyond
  • Compatible with DOTA-based ligands (e.g., DOTATATE, PSMA)
Half-Life
6.9 days
Decay Scheme
100% β- decay to Dysprosium-161 (Dy-161)
Radionuclidic Purity (gamma spectrometry)
161Tb >99.9%; 160Tb ≤ 0.01%
Chemical form
Tb3+ in aqueous 0.05 M HCl solution
Radioactivity concentration at ART (Dose calibrator)
90 – 110 % of the activity stated on the label
Appearance (visual)
Clear and colourless solution
Identity 161Tb (gamma spectrometry)
48.92 keV gamma line existing
57.2 keV gamma line existing
74.58 keV gamma line existing
87.93 keV gamma line existing
103.07 keV gamma line existing
pH value (pH indicator strip)
1.0 – 2.0
Identity chloride (Ph. Eur.)
White precipitate visible
Chemical purity (ICP-MS): corrected to Tb-161 activity at ART
Fe : ≤ 0.25 µg/GBq
Cu : ≤ 0.5 µg/GBq
Zn : ≤ 0.5 µg/GBq
Pb : ≤ 0.5 µg/GBq
160Gd : ≤ 0.14 µg/GBq
Sum of impurities ≤ 0.5 µg/GBq
Radiochemical purity (TLC)
≥ 99.0% as 161TbCl3
Radiolabeling yield (TLC)
≥ 99.0% (Based on radiolabeling of 161Tb with DOTATATE molar ratio 1:4)

Tb-161 Orders/Questions

For ordering information or questions, use the form below or call us at 208.524.5300.

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