Fast Atom Bombardment-Mass Spectrometry

Mass spectrometry (MS) is a chemical analytical technique that can yield data in the form of a spectrum of peaks of differing relative intensities and over a range of mass-to-charge (m/z) values. Such data permit calculation of molecular weight and molecular structure. The technique has been used widely in microbiology for many years. Molecules are separated in a high vacuum electromagnetic field following ionization which traditionally was by electron impact (EI) or by chemical ionization (CI) with a reagent gas. Recently, a new method for ionization of analyte has been devised, fast atom bombardment (FAB). The latter uses large atoms, such as xenon, to ionize solute by transfer of collisional energy.