Copper-63

Main isotopes of copper

iso NA half-life DM DE (MeV) DP 63Cu 69.15% is stable with 34 neutrons 64Cu syn 12.70 h ε – 64Ni β− – 64Zn 65Cu 30.85% is stable with 36 neutrons 67Cu syn 61.83 h β− – 67Zn
Standard atomic weight (Ar)	63.546(3)

Copper (₂₉Cu) has two stable isotopes, ⁶³Cu and ⁶⁵Cu, along with 27 radioisotopes. The most stable of these is ⁶⁷Cu with a half-life of 61.83 hours. The least stable is ⁵⁴Cu with a half-life of approximately 75 ns. Most have half-lives under a minute. Unstable copper isotopes with atomic masses below 63 tend to undergo β⁺ decay, while isotopes with atomic masses above 65 tend to undergo β⁻ decay. ⁶⁴Cu decays by both β⁺ and β⁻.

⁶⁸Cu, ⁶⁹Cu, ⁷¹Cu, ⁷²Cu, and ⁷⁶Cu each have one metastable isomer. ⁷⁰Cu has two isomers, making a total of 7 distinct isomers. The most stable of these is ^68mCu with a half-life of 3.75 minutes. The least stable is ^69mCu with a half-life of 360 ns.

Copper offers a relatively large number of radioisotopes that are potentially suitable for use in nuclear medicine.

There is a growing interest in the use of ⁶⁴Cu, ⁶²Cu, ⁶¹Cu, and ⁶⁰Cu for diagnostic purposes and ⁶⁷Cu and ⁶⁴Cu for targeted radiotherapy. For example, ⁶⁴Cu has a longer half-life and is thus ideal for diagnostic PET imaging of biological molecules.

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