Analysis of underivatized polyamines by reversed phase liquid chromatography with electrospray tandem mass spectrometry

A reversed phase liquid chromatography–electrospray ionization-tandem mass spectrometric method (RP-LC–ESI-MS/MS) was developed to separate and detect polyamines with minimal sample pre-treatment and without any derivatization. Prior to MS/MS analysis, a complete chromatographic separation of polyamines was achieved by a linear gradient elution using heptafluorobutyric acid as a volatile ion-pair modifier, and signal suppression was prevented by post-column addition of 75% propionic acid in isopropanol to the column flow. The developed method was successfully applied to the identification of metabolites formed from N1,N12-diethylspermine in the reaction catalyzed by recombinant human polyamine oxidase and to the detection of eight different polyamines in a standard mixture.