SECONDARY-ION MASS-SPECTROMETRY OF GLYCOSYLATED PORPHYRINS

Solid secondary ion mass spectrometry (SIMS) has been used to study a series of acetylated precursors of glycosylated porphyrins in the course of their synthesis. Characteristic positive and negative spectra have been readily obtained for all the compounds up to more than 2000 Da. In addition to the protonated or deprotonated molecules, fragment ions arising from cleavages between the oxygen atom of the ether bond and the acetylated sugar units were observed; these fragments were more abundant in the negative spectra. The solid SIMS spectra are not complicated by chemical noise or chemical reactions occuring in the presence of a matrix which makes the method well suited for rapid screening during synthesis.