STATIC SECONDARY-ION MASS-SPECTROMETRY (SSIMS) OF BIOLOGICAL COMPOUNDS IN TISSUE AND TISSUE-LIKE MATRICES

This paper presents results of a static secondary ion mass spectrometr y (SSIMS) study of molecular, pseudo-molecular and structurally signif icant fragment ion peaks produced from an extensive list of biomolecul es analyzed as neat residues and as components in biological matrices. This study defines realistic detection limits for analysis of represe ntative pharmaceutical compounds incorporated into tissue or tissue-li ke matrices using state-of-the-art time-of-flight secondary ion mass s pectrometry (TOF-SIMS) techniques. Detection limits on the order of 10 0-1000 parts-per-million (ppm) are observed under typical analytical c onditions in which the analysis areas are approximately 200 micrometer (mu m) in diameter and analysis depths are 1 to 2 monolayers. Represe ntative secondary ion images of selected biomolecules are also present ed and relationships between image resolution, mass resolution and det ection sensitivity are discussed. (C) 1997 Elsevier Science B.V.