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Naturally occurring lutetium (71Lu) is composed of one stable isotope 175Lu (97.41% natural abundance) and one long-lived radioisotope, 176Lu with a half-life of 3.78 × 1010 years (2.59% natural abundance). Thirty-five radioisotopes have been characterized, with the most stable, besides 176Lu, being 174Lu with a half-life of 3.31 years, and 173Lu with a half-life of 1.37 years. All of the remaining radioactive isotopes have half-lives that are less than 9 days, and the majority of these have half-lives that are less than half an hour. This element also has 18 meta states, with the most stable being 177mLu (t1/2 160.4 days), 174mLu (t1/2 142 days) and 178mLu (t1/2 23.1 minutes).

Lutetium (177Lu) chloride is a radioactive compound used for the radiolabeling of pharmaceutical molecules, aimed either as an anti-cancer therapy or for scintigraphy (medical imaging). It is an isotopomer of lutetium(III) chloride containing the radioactive isotope 177Lu, which undergoes beta decay with a half-life of 6.65 days.

Lutetium (177Lu) chloride is a radiopharmaceutical precursor and is not intended for direct use in patients. It is used for the radiolabeling of carrier molecules specifically developed for reaching certain target tissues or organs in the body. The molecules labeled in this way are used as cancer therapeutics or for scintigraphy, a form of medical imaging. 177Lu has been used with both small molecule therapeutic agents (such as 177Lu-DOTATATE) and antibodies for targeted cancer therapy.

Spectrum (Fullscreen1, Fullscreen2)

Spectrum of 177mLu and 177Lu in a sample. 5 minute measurement with a High Purity Germanium (HPGe) radiation detector.

This sample has been cleaned of 177mLu, therefore the peaks are 177Lu only. 5 minute measurement with a High Purity Germanium (HPGe) radiation detector.


Isotope: Lutetium
Mass number: 177
Atomic number: 71
Neutron number: 106

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