JГјrgen H Gross - Mass Spectrometry

The first instrument to separate ions by mass-to-charge ratio was constructed by Joseph John Thomson (Nobel Prize in physics in 1906 for the discovery of the electron) in his attempt to understand electric discharges in gases and to analyze the charged gas phase species involved. His work [). While Thomsons original book from 1913 is hard to come by, there is a reprint by the American Society for Mass Spectrometry (ASMS) that is readily available.

Particularly due to Francis William Astons work in the following decade, the new revolutionary technique soon provided means for the atomic characterization of numerous elements []. Further Nobel Prizes related to MS are tabulated in the Appendix.

Thomsons apparatus, the parabola spectrograph , employs parallel magnetic and electric fields to achieve a deflection of ionic species depending on charge sign, charge, and mass. Ions exiting the ion source are passed through a collimator to create a roughly parallel beam that is then sent into the analyzer (Fig..)

Thomson and Aston only marked the beginnings of what expanded into more than a century of exciting developments in mass spectrometry, the major milestones of which were recently compiled [].

The pioneering mass spectrometrist worked with home-built rather than commercial instruments. These machines, typically magnetic sector instruments using electron ionization, delivered a few mass spectra per day, providing that the device was delicately handled. Intimate knowledge of such an instrument and interpretation skills of the according EI spectra would provide the mass spectrometrist with a previously unknown wealth of insight into structural details []. The life sciences, in particular, have provided a great impetus for new developments that expand the mass range to higher molecular weights and increasingly fragile molecules. Environmental and pharmaceutical research has been a driving force in reaching even lower limits of detection. Current research is aimed at methods of ion sampling, ion generation, and subsequent ion transfer into mass analyzers for superior performance.