Mass spectra of disodium pamoate and an isomer by electron, chemical and fast atom bombardment ionisation

Abstract

The El and Cl spectra of these two isomeric salts contained few high mass peaks. The positive and negative FAB spectra showed [M + H]⁺ and [M – H]^– ions, respectively (where M is the disodium salt). Other strong peaks related to the structure were seen in the relative molecular mass region. The FAB spectra are useful for identifying these salts. For each ionisation technique there were differences between the spectra of the two isomers, but the major differences were observed in the El and Cl spectra. Either El or Cl spectra would be useful for differentiating these isomers.