ESI-MS as a tool for understanding the performance of Z- and E-synapinic acids as MALDI matrices at molecular level: Study of complexes with carbohydrates.

TOBÍAS SCHMIDT DE LEÓN; MARÍA LAURA SALUM; YASUYUKI MATSUSHITA; KAZUHIKO FUKUSHIMA; MARÍA EUGENIA MONGE; ROSA ERRA-BALSELLS

Rio de Janeiro

Congreso; III IberoAmerican Conference on Mass Spectrometry; 2022

E-3,5-dimethoxy-4-hydroxycinnamic acid, sinapinic acid (ESA), have enabled thesuccessful application of matrix-assisted laser desorption/ionization mass spectrometry (MALDIMS) for various analytes [1]. The presence of a rigid double bond in the structure of cinnamic acidsleads to the existence of two geometric isomers E and Z. In particular Z-3,5- dimethoxy-4-hydroxycinnamic acid (ZSA) has proven to be a more efficient matrix for the study of low molecularweight carbohydrates (Carb) compared to the E isomer [2]. Molecular modeling studies have shownthat the interactions between the matrix and the analyte change dramatically as a consequence of thechange in the stereochemistry of the cinnamic acid double bond [2]. These studies show theformation of non-covalent 1:1 complexes, with [ZSA+Carb] complexes being more stable than[ESA+Carb] complexes due to the greater number of intramolecular hydrogen bridge typeinteractions [2]