Properties of Useful Radioactive Copper Isotopes

There are two useful radioactive isotopes of copper. Certain properties of these are shown in Table 2. 

Copper-64 is readily available commercially, and so far has been more widely used than Cu . Its half-life is short and it therefore can be used only for relatively short-term experiments. By virtue of positron emission, it yields two rather energetic y-rays through an annihilation reaction which can be detected and measured with relatively high efficiency. 

Copper-67 (not available commercially) has been produced and used for some experiments (S44). Its half-life is longer than that of Cu and it is also readily measured by its 7-emission. The energy peaks of Cu and Cu are conveniently different, which permit their use in double-labeling experiments (S44). 

Both Cu and Cu emit /3-radiation thus they can be measured by /3-counting techniques and detected by autoradiography. Unfortunately, their maximum /8-energy is rather high and the autoradiographic resolution therefore is rather poor, which impairs their suitability for microautoradiography. 

Copper-64 of a medium degree of specific activity can be produced by bombarding Cu , one of the stable copper isotopes, with thermal neutrons to yield Cu by the following reaction. 

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