A simple desalting procedure for fast atom bombardment mass spectrometry

Abstract

A simple and efficient procedure for desalting samples prior to fast atom bombardment mass spectrometry utilizes low-pressure reverse-phase chromatography with disposable high-capacity mini-columns. Microscale (0.1–10 μmol) sample purification with high analyte recovery is possible for nucleosides, nucleotides and peptides. Salt removal has been evaluated both by conductivity and mass spectral methods and is greater than 99% for the model compounds cytidine, adenosine and AMP, even when they are contaminated with a 10 molar excess of NaCl. This procedure is also applicable to a range of small peptides as demonstrated with pyro-Glu-His-Gly and methionine enkephalin.