A history of isotope ratio mass spectrometry

The history of isotope ratio mass spectrometry and the terminology adopted by this specialised branch of mass spectrometry is discussed, with special reference to doping control. Writing in Drug Testing and Analysis, Ulrich Flenker from the German Sports University Cologne describes the progress in the technique from its inception in 1940s to the present day, although the basic design of the instruments has remained fairly constant. The importance of the continuous-flow interface, which allows coupling to other analytical devices such as gas chromatographs, is emphasised.

Compound-specific isotope analysis (CSIA) in doping control is currently used exclusively for steroids to allow source assignment. The meanings of terms such as source assignment, source apportionment, endogenous and synthetic steroids are also discussed and recommendations are made to avoid confusion.