MATRIX SELECTION FOR LIQUID SECONDARY-ION AND FAST-ATOM-BOMBARDMENT MASS-SPECTROMETRY

This chapter describes the critical parameters necessary in the selection of an appropriate matrix for liquid secondary ion mass spectrometry (LSIMS) and fast atom bombardment (FAB) mass spectrometry. Requirements for acquisition of full mass spectra are considered. Dedicated matrix properties for applications of tandem mass spectrometry are also evaluated. Most of the so-called “soft” ionization methods yield molecular weight as well as structural information. Semiquantitative analysis can be performed once the relation between the signal from the target compound and its concentration is not modified by matrix effects. As a consequence, except for specific applications, the choice of an ionization method for fragile molecules analysis will be guided mainly by its ease of implementation and operation on multipurpose mass spectrometers. The complexity of many biological or environmental samples necessitates the separation of their components prior to analysis. In addition, a time concentration effect (as in chromatography) allows large gains in sensitivity for analytes present in trace amounts. © 1990, Elsevier Inc. All rights reserved.