Isotopic Distributions

Alan L Rockwood1, Magnus Palmblad2

  • 1Department of Pathology, University of Utah, Salt Lake City, UT, USA.

Summary

Mass spectrometry uses isotopic information for passive applications like chemical analysis and active applications such as isotope tracing. Calculating theoretical isotopic patterns is crucial for both, enabling diverse scientific investigations.

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In the early 1900s, English chemist Frederick Soddy realized that an element could have atoms with different masses that were chemically indistinguishable. These different types are called isotopes — atoms of the same element that differ in mass. Isotopes differ in mass because they have different numbers of neutrons but are chemically identical because they have the same number of protons. Soddy was awarded the Nobel Prize in Chemistry in 1921 for this discovery.
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