Chrys Wesdemiotis
University of Akron, USA
Title: Multidimensional Mass Spectrometry Methods for Synthetic Polymer Analysis
Biography
Biography: Chrys Wesdemiotis
Abstract
Matrix-assisted laser desorption ionization and electrospray ionization have enabled mass spectrometry (MS) analyses for a wide variety of synthetic polymers, but considerable challenges still exist. Polymerizations often create complex mixtures that are impossible to characterize by single-stage MS because of superimposed compositions or discrimination effects in the ionization or detection steps. These problems can partly be resolved by tandem and multistage mass spectrometry (MS2); depending on the polymer, MS2 may lead to fragmentation patterns that permit unequivocal identification of the corresponding architecture and comonomer sequence. For the characterization of more complex systems, MS must be combined with separation methods, such as liquid chromatography (LC) or ion mobility (IM) spectrometry. Particularly powerful for such studies are approaches that couple ultrahigh performance LC (UPLC), which significantly reduces elution times, with the ion mobility dimension, which enhances separation and spectral decongestion. Different combinations of LC, IM, and MS2 can be used to address questions about polymer composition, structure, and 3D architecture. Analyses involving top-down methods (the entire analysis is performed in the mass spectrometer) as well as methods including prior LC separation or mild, in situ thermal desorption/degradation will be demonstrated with a variety of synthetic polymers, including new amphiphilic copolymers, hybrid materials containing bioactive peptides, and supramolecular systems.