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Electro-spray Ionization Mass Spectrometer

  • Made in New Haven, Connecticut
  • 71 in. H x 65 in. W x 40 in. D
    Metal, plastic, copper, rubber
  • On display in Making Modernity
  • Gift of Dr. John Fenn
  • 2005.141A


This very sophisticated mass spectrometer was built by Dr. John Fenn and his graduate students at Yale University to study Electro-Spray Ionization Mass Spectrometry. This technique ionizes large biological molecules (macromolecules) and then analyzes them with a typical mass spectrometer. Until Fenn invented this instrument, macromolecules were extremely difficult to measure owing to their size and complexity. Dr. Fenn shared the 2002 Nobel Prize in Chemistry with Koichi Tanaka “for their development of soft desorption ionization methods for mass spectrometric analyses of biological macromolecules.”



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Arnold O. Beckman

CHF’s Beckman Center for the History of Chemistry was started with a generous grant from the Arnold and Mabel Beckman Foundation in 1987.



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