Formation of the [M+NH₄]⁺ ions of some mono-and di-saccharides in fast atom bombardment mass spectrometry

Abstract

In positive-ion fast atom bombardment (FAB) mas spectrometry, the abundance of [M+H]⁺ ion of mono- and di-saccharides is too low to allow determination of their molecular weights. However, when mono- and di-saccharides are mixed with an appropriate amount of NH₄Cl, a highly abundant peak [M+NH₄]⁺ appears in FAB mass spectra. From the adduct ion [M+NH₄(the molecular weights of mono - and di-saccharides can be determined definitively. Here, twelve monosaccharides and six disaccharides have been studied.