Bioanalytical Mass Spectrometry

Josh Dubin


Mass spectrometry works by simultaneously vaporizing and ionizing molecules, and then separating them according to differences in their mass to charge ratios. A variety of methods and instruments are employed for the ionization and separation processes, depending on the molecules being analyzed. Each method of separation essentially works because ionized molecules can be separated in space or time by an induced acceleration that is reflective of the mass/charge ratio of each molecule. Five techniques of mass spectroscopy utilizing different ionization and separation methods are as follows. For an overall explanation of mass spectrometry, take a look at Scimedia's entry on MS. The links below will automatically bring you to the Scimedia's entries on each type of MS instrument.

Fourier-transform MS
Ion-trap MS
Magnetic-sector MS
Quadrupole MS
Time-of-flight MS


Bioanalytical chemists have taken mass spectroscopic analyses into the realm of large biomolecules, including proteins, oligonucleotides, and carbohydrates. Mass spectrometry allows the identification of biomolecules without the use of wet chemical techniques that would necessarily require larger samples. When dealing with quantities of proteins or nucleotide sequences present within single cells, mass spectrometry is an optimal, often automated identification technique.

Biomolecules, however, require a slightly altered version of the spectrometry process, because polymeric integrity should be maintained. Most ionization techniques cause the fragmentation of molecules before they are detected, and this is often an integral component of the identification process. However, for amino acid and nucleotide sequences, proteases and nucleases are used to fragment the polymers into predictable fragments, and these fragments are then chemically ionized so as to not cause further fragmentation. This allows the mass spectra to be pieced back together to reveal sequence information. Protocols for protein identification by mass spectrometry are outlined at PROWL's site.

For further information and some research on biomolecule identification by MS, or if you can't imagine how mass spectrometry and the National Rifle Association are related, take a look at Justin Hettick's MS Page.

Base Peak is a site that is dedicated to mass spectrometry, provided by a leading publisher in the subject. Journal databases, books, and links to other MS sites are included.

For questions and access to a mass spec newsgroup, see sci.techniques.mass-spec Homepage (look under Biochemistry Topics for archives).

Student MS Laboratories & Literature Reviews on MS