It was found earlier that under matrix-assisted laser desorption/ionization (MALDI) conditions several organic compounds which produce adduct with silver ions, are also capable of forming adducts with Ag3+ cluster ions under appropriate conditions. The Ag3+ cluster ion can be in situ generated under the MALDI analysis conditions from silver trifluoroacetate cationization agent in the presence of organic MALDI matrices. In this article the fragmentation of a commercial plasticizer, a peracetylated isoflavone glycoside and a pyrazolylphenyl disulfide derivative cationized with silver ions and Ag3+ cluster ions are compared. It was observed that the complexes of Ag3+ are less fragmented than the corresponding adduct ions with Ag+. The presumable fragmentation channel of [M + Ag3+] is the elimination of Ag2 units from these complexes. No significant dissociation of [M + Ag3+], into M and Ag3 + takes place, indicating a tight connection between the corresponding molecule and Ag3+ cluster ion. However, with a compound carrying very labile groups, such as the pyrazolylphenyl disulfide derivative, intramolecular cleavages can occur prior to significant dissociation of the Ag3+ cluster ion.
|Number of pages||5|
|Journal||Journal of the American Society for Mass Spectrometry|
|Publication status||Published - Jun 1 2004|
ASJC Scopus subject areas
- Structural Biology