Organizers: Gary Patterson, Michael Grayson
Natural history of positive electricity / Gary D. Patterson
Since antiquity it was known that some objects attracted one another and other objects repelled one another. Benjamin Franklin was able to unify the 18th century understanding of electrical phenomena by invoking two kinds of electricity. Joseph Priestley ended the century with further explanations and unifications. Michael Faraday was able to study electric current inside vacuum tubes and the electromagnetic theory of Maxwell stimulated a search for the fundamental sources of negative and positive current. Jean Perrin studied the behavior of Crooke's tubes and determined that the current was carried by negative particles. J.J. Thomson subjected these particles to magnetic fields and the "electron" was born. But, if electrons were going in one direction, what was going in the other direction to equalize the charge? Sure enough, there were cations in Crooke's tubes as well: rays of positive electricity!
True origin of the first mass spectrometer / O. David Sparkman
Was J.J. Thomson's 1913 book Rays of Positive Electricity the first monograph to report what has become known as “the mass spectrometer”? Francis William Aston was awarded the 1922 Nobel Prize in Chemistry in part for the development of a mass spectrograph. Thomson first observed that neon produced two separate signals in his rays of positive electricity apparatus, but he was not able to say what they were. Aston recognized what the singles represented and capitalized on this. This presentation will attempt to answer those questions that come up in every course on mass spectrometry of who and when was the mass spectrometer developed. One hundred years after what is considered to be the first mass spectrometry book was published, the question is still a question, until now; maybe.
Isotopes: The era of the physicist / Michael A. Grayson
The story of isotopes and mass spectrometry begins with J. J. Thomson who observed a line at mass 22 in the positive ray analysis of neon in 1912. Interestingly, while Thomson accepted the existence of isotopes among the radionuclides, he held firmly to the belief that stable elements were monoisotopic. In truth, we should credit Aston with the discovery of isotopes of the stable elements – as he was when awarded the Nobel Prize in Chemistry in 1922. Aston chose the exploration of isotopes of the elements as his primary research enterprise; and began by creating a new and improved positive ray analyzer. His competitor and colleague in this enterprise was A. J. Dempster, an expatriate Canadian at the University of Chicago, who – developing his own mass analyzer – was the first to report the isotopes of several elements, mainly because he did not feel the need to use gas discharge as the only method of sample ionization. As the importance of Einstein's classic equation relating energy and mass became more widely understood, the physics community was intent on determining the exact masses and relative abundance of the isotopes for all of the elements. This was a strong motivator for the design and construction of mass analyzers capable of ever more precise mass determinations as well as accurate abundance measurements. Nier joined this group of physicists in 1935 when he reported a previously unknown isotope of potassium. Both Dempster, Bainbridge and Nier made important contributions to the understanding of nuclear fission in uranium. While physicists dominated this endeavor, we can credit a petroleum chemist, Meyerson, for prompting the physics community to revisit and correct the relative abundance of chlorine isotopes in 1961.
MS/MS: From Thomson's day to ours / R. Graham Cooks
Collision-induced dissociation has been known almost as long as mass spectrometry. This presentation covers the history of this subject, from early adventitious observations through systematic studies of the kinematics and dynamics of inelastic ion/molecule in/surface collisions over a range of collision energies, through the development of collision-induced dissociation as a method of characterization of ions to the examination of individual constituents of complex mixtures using tandem mass spectrometry. The later development of alternatives to collision-induced dissociation is also mentioned. The talk can be summarized by the acronyms related to the methodology: m*, MIKES, MS/MS, MRM, SID, etc. and alternatively by the people mostly responsible for these developments –White, Jennings, McLafferty, Futrell, etc.
Time-of-flight mass spectrometry: From niche to mainstream / Ken G. Standing
World war II electronic advances suggested the use of time-of-flight for mass measurements (Stephens), and subsequently to the development of commercial TOF instruments by Bendix and by Bioion (TOF/PDMS/MacFarlane), as well as to the use of TOF/SIMS (Standing). Although the latter TOF methods were the only ones capable of measuring the masses of really large biomolecules, most mass spectrometrists were still wedded to sector/quadrupole instruments for high/low-end mass measurements. The coup-de-grâce for TOF (as generally believed) was the discovery (Barber1981) of a suitable matrix (glycerol), which enabled the use of sector/quadrupole instruments for measurements of large biomolecules (“fabulous FAB”). Ironically, it was the discovery of suitable matrices for laser excitation (MALDI/Hillenkamp/Karas) that revived TOF, aided by the additional accuracy provided by the reflecting geometry (Mamyrin), and the subsequent development of orthogonal injection (Dodonov). Thus TOFMS/MALDI, along with electrospray, are the prime methods now used for the mass spectrometry of biomolecules.
Ever-widening horizons of biological mass spectrometry / Catherine E. Costello
Physicists and physical chemists started the field of mass spectrometry (MS) and the petroleum industry promoted development of commercial instrumentation, but it is mass spectrometry's relevance to biology and medicine that has propelled much of its growth and public attention. MS defines biochemical pathways, taking particular advantage of stable isotope-labeled tracers. Early work that focused on drug metabolism and toxicology has led to critical roles in sports competitions and forensics. MS enabled amino acid sequencing of peptides and precise structural determinations of steroids, glycans, oligonucleotides, toxins and perfumes; today it is the fundamental approach for proteomics, glycomics, lipidomics, metabolomics and dynamic imaging. The needs of biological MS have motivated increases in mass range, scan speed, sensitivity, resolution and mass accuracy; today's amazing instruments are capable of analyzing vanishingly small amounts of materials that are components of extremely complex mixtures, well beyond the imagination and dreams of early practitioners.