Larson Lecture: Meandering Through Mass Spectrometry

Dr. Burnaby Munson University of Delaware

Date & Time:

Thursday, September 27, 2018
7:30 PM - 8:30 PM

Abstract

Mass spectrometry began with the work of Sir J. J. Thomson {Nobel Prize, Physics, 1906}, probably with his 1913 monograph, RAYS OF POSITIVE ELECTRICITY and their application to CHEMICAL ANALYSIS. One of his earliest observations was that of a positive ion of mass 3, H3+. This somewhat unusual and highly reactive ion has been observed in interstellar space and is a likely precursor in the formation of molecular species.

Radioactive decay {Marie & Pierre Curie, Nobel Prize, Physics, 1903} had shown species that were not chemically separable, but the existence of isotopes {Richards, Nobel Prize, Chemistry, 1914 and Soddy, Nobel Prize, Chemistry, 1921} in “ordinary” atoms was not clearly established until mass spectrometric determinations {Aston, Nobel Prize, Chemistry, 1922}. Isotope ratio mass spectrometry, IRMS, has been developed into an analytical tool in archeology, geology, and environmental and forensic chemistry.

Analytical (mostly organic) mass spectrometry began in the 1950s with the first commercial instruments – initially in oil company laboratories and then almost everywhere. Initial commercial mass spectrometers were large, with heavy magnets. Now many types of mass analysis are used and mass spectrometers have been successfully used in interplanetary missions.

One of the goals in mass spectrometry has been to increase the range of molecular weights and molecular complexity of compounds that could be analyzed. Different ionization procedures and types of mass analysis have been developed: FAB, FIB, SIMS, LDI, Fission Fragment Desorption, MALDI, ESI, MAI, TOF, FTICR. The developers of MALDI (Tanaka) and ESI (Fenn) were awarded the Nobel Prize in Chemistry in 2002. Mass spectra of high molecular weight polymers and sequencing proteins are now “old hat”. Ion mobility spectrometry, IMS, or ion mobility mass spectrometry, IMMS, is used for detection of explosives/narcotics in airport security and to determine the shapes of peptides.

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