The Analysis of Polysulfonated Azo Dyestuffs by Matrix-assisted Laser Desorption/Ionization and Electrospray Mass Spectrometry

Electrospray ionization and matrix-assisted laser desorption/ionization have been applied to the analysis of polysulfonated azo dyestuff mixtures. Three homologous orange dyestuffs were synthesized using a harsh, two-stage process involving a condensation followed by a reduction and, producing complex product mixtures. The negative-ion spectra provide clear molecular weight information for the components of the mixtures containing five or six sulfonic acid groups, allowing rapid identification of product composition at both the condensation and reduction stages of synthesis.