Foreword
Shortly after having graduated in 1966 and just employed as a research assistant in
a protein chemistry laboratory, my very first contact with mass spectrometry hap-
pened when I stumbled on a paper by Michael Barber, the later discoverer of fast
atom bombardment (FAB). Together with a French group he had determined the
covalent structure of an almost 1.4 kDa complex peptidolipid called fortuitine by
using mass spectrometry. Fascinated by this to me unknown technique, I felt that
MS would be a future key analytical method in protein studies. At that time, the
only ionization method available was electron ionization, which required a sample
to be in the gaseous state in the ion source. Therefore most mass spectrometric
analyses were dealing with small organic molecules – and peptides and proteins
were not volatile. Fortuitine was a very fortuitous sample, because it was naturally
derivatized with the consequence that it could be volatilized into the ion source.
Nevertheless, I went into mass spectrometry. My first mass spectrometer was in-
stalled in our laboratory in 1968. Mass spectrometers at that time were complex
fully manually operated instruments most of them magnetic/electrostatic sector in-
struments, and the operator needed to know the instrument well in order to avoid
catastrophes by opening wrong valves at the wrong moment. Spectra were re-
corded on UV paper with a galvanometer recorder or on photographic plates and
mass assignment was performed manually. During the 1970s a number of new
ionization methods and mass analyzers became available. These included ioniza-
tion by chemical ionization and by field ionization/desorption as well as mass
analyses by quadrupoles and ion traps. Computers became available for data ac-
quisition and mass assignment. Life became easier but the requirement for volatile
samples was still there.
The 1980s revolutionized the possibilities for mass spectrometric analysis. In
the early half of the decade introduction of FAB and commercialization of the 10
years earlier developed plasma desorption mass spectrometry allowed for analyses
of nonvolatile samples such as peptides, proteins, and nucleic acids. The first
commercial fully automated mass spectrometer, the BioIon plasma desorption
mass spectrometer, became available and the time-of-flight analyzer, which had
unlimited mass range, was revived. Late in the decade the two new and now
dominating ionization methods electrospray ionization (ESI) and matrix-assisted
laser desorption ionization (MALDI) were introduced. These two ionization meth-
ods opened a new era for mass spectrometry. Now all the large nonvolatile bio-
logical molecules could be analyzed. Till then GC-MS had been extensively used
for analysis of complex mixtures in environmental and clinical sciences, but due
to its nature it was limited to small volatile molecules. ESI made coupling of LC
with MS possible allowing for entirely new applications of mass spectrometry.
Proteomics now became a big move forward with mass spectrometry as the key
analytical tool. Thousands of scientists took up mass spectrometric analysis and
