Oxygen-17

Oxygen-17 is a low abundant isotope of oxygen (0.0373% in seawater; approx. twice as abundant as Deuterium). Being the only stable isotope of oxygen possessing a nuclear spin(+5/2) and a favorable characteristic of field-independent relaxation in liquid water, this enables NMR studies of oxidative metabolic pathways through compounds containing ¹⁷O at high magnetic fields (i.e. metabolically produced H₂¹⁷O water by oxidative phosphorylation in ).

The isotope was first hypothesized and subsequently imaged by Patrick Blackett in Rutherford's lab 1924:

Of the nature of the integrated nucleus little can be said without further data. It must however have a mass 17, and provided no other nuclear electrons are gained or lost in the process, an atomic number 8. It ought therefore to be an isotope of oxygen. If it is stable it should exist on the earth.

It was a product out of the first man-made transmutation of ¹⁴N and ⁴He²⁺ conducted by Frederick Soddy and Ernest Rutherford in 1917-1919. Finally its natural abundance in earth atmosphere was detected in 1929 by Giauque and Johnson in absorption spectra.

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