The 2007 Benjamin Franklin Medal in Chemistry Presented to Klaus Biemann, Ph.D., of The Massachusetts Institute of Technology Cambridge, Massachusetts

Mass spectrometry is an analytical technique used to measure mass and the structure of complex organic compounds. Mass spectrometry had its origins in J.J. Thomson's vacuum tube, with which, in the early part of the 20th century, the existence of electrons and "positive rays" was demonstrated. Thomson, the physicist, observed in his book "Rays of Positive Electricity and Their Application to Chemical Analysis" that the new technique could be used profitably by chemists to analyze chemicals. Despite this far-sighted observation, the primary application of mass spectrometry remained in the realm of physics; the technique was used to discover a number of isotopes, to determine the relative abundance of the isotopes, and to measure their "exact masses", i.e. atomic masses, with high precision. America's entry into WWII moved mass spectrometry out of the physics laboratory into industrial settings. War-time needs included using mass spectrometry for the analyses of petroleum distillates: determination of high octane fuels; analyses of synthetic rubbers for vehicles, planes and other uses.