An introduction to electrospray ionization and matrix-assisted laser desorption/ionization mass spectrometry: Essential tools in a modern biotechnology environment

The tremendous progress in biochemistry and biotechnology has been made possible in part by recent advances in analytical methods, in particular mass spectrometry. With the introduction of electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI), mass spectrometry allowed the determination of the molecular weight of peptides and proteins with a much greater accuracy than achievable by traditional methods such as SDS-PAGE and biogel chromatography. In addition, these mass spectrometry experiments have become routine and can be performed within minutes. ESI and MALDI (in combination with enzymatic methods) can also provide vital structural data such as the amino acid sequence and the sites of posttranslational modifications for peptides and proteins with a sensitivity that competes favorably with other methods. The use of ESI and MALDI is not limited to peptides and proteins; analysis of oligonucleotides and oligosaccharides has been simplified by these techniques as well. For information about structurally significant noncovalent interaction between various types of biomolecules, ESI is probably one of the most convenient methods. Not surprisingly, we anticipate that the mass spectrometers with these ionization capabilities will soon become standard equipment in all pharmaceutical and biotechnology laboratories. (C) 1997 John Wiley & Sons, Inc.