Derivatization in Mass Spectrometry—6. Formation of Mixed Derivatives of Polyfunctional Compounds

Abstract

The review describes chemical transformations of multifunctional compounds (amino acids and peptides, amino alcohols, amino thiols, hydroxy acids, oxo acids, oxo alcohols, compounds containing simultaneously three or more different groups etc.) by using step-wise or one-step modification or protection of functional groups. Some chemical aspects of mixed derivatization performed for improving the physical-chemical properties and mass spectral characteristics are discussed. Application of mixed derivatization to qualitative and quantitative analysis of various multifunctional compounds mainly in biological fluids and other matrices by gas chromatography/mass spectrometry in electron ionization, chemical ionization, negative-ion chemical ionization and selected ion monitoring modes is considered.

Mass Spectrometric Fragmentation of Trimethylsilyl and Related Alkylsilyl Derivatives

“…This review covers the fragmentation mechanisms displayed by these derivatives in studies using mainly GC/MS. It is beyond the scope of this review to include methods for preparation of TMS and related derivatives; these methods are well covered in text books (Blau & Halket, ; Knapp, ; Pierce, ; van Look, ; Zaikin & Halket, ) and recent reviews (Halket & Zaikin, ; Halket & Zaikin, ; Poole, ; Zaikin & Halket, ).…”

Multiparametric analysis of amino acids and organic acids in rat brain tissues using GC/MS

“…In this study, in order to avoid generating the partial derivatization products and hampering compound identification and quantification, we adopted ECF derivatization for GC/MS assay [21]. With such a procedure, we attempted to probe subtle variation among different parts of the brain tissues such as cerebral cortex, hippocampus, and thalamus.…”

Why do we need chemical derivatization?

“…Another set of derivatization reactions is used to improve the separation and to ease the identification in chromatographies (gas as well liquid). In mass spectrometry, derivatization allows one to obtain more information about the structure of the analyzed molecule, like the position of a particular functional group in the molecule . These are only a few examples of the applications of derivatization techniques.…”