Sequencing of underivatized peptides by direct liquid inlet liquid chromatography mass spectrometry

Biochemical applications of liquid chromatography-mass spectrometry

The current state-of-the-art liquid chromatography-mass spectrometry (LC-MS) is reviewed with particular attention to biomedical applications. The most common LC-MS interface designs are described and compared. These interfaces include transport, direct liquid introduction, thermospray, atmospheric pressure ionization, monodisperse aerosol generation, open-tubular LC and continuous-flow fast atom bombardment. The relative sensitivities of the techniques are compared as much as possible, as well as their tendencies to induce thermal decomposition of the sample. Applications of these various interface types to a variety of biomedically important compound classes, including peptides, nucleotides, steroids, lipids, carbohydrates, xenobiotic metabolites and drugs, are also reviewed.

Automated dry fraction collection for microbore high-performance liquid chromatography-mass spectrometry

A method is presented for the collection of dry fractions from a microbore high-performance liquid chromatographic column. These fractions are electrosprayed onto a foil strip that is being moved past the spray in steps. These solid deposits are in a form which is compatible with solid-phase secondary-ion mass spectrometry, in particular the time-of-flight instrument that has been developed in our laboratory. Because the type of ionization used in static secondary-ion spectrometry is essentially non-destructive, the non-volatile eluent is available for any other analytical method after mass analysis. The chromatogram of a mixture of peptides was re-constructed from the mass spectra of fractions collected in this way. This chromatogram is shown and its features are examined.