title: Size dependence of the folding of multiply charged sodium cationized polylactides revealed by ion mobility mass spectrometry and molecular modelling.
abstract: Ion mobility spectrometry coupled with mass spectrometry was used to experimentally determine the three-dimensional structure of multiply charged sodium cationized polylactides (PLA). In particular, the experiments were conducted to evaluate the influence of the charge state and the size on the gas-phase conformation of cationized PLA. The measured collision cross sections were then compared to calculated values obtained by computational chemistry methods. The most striking feature was the experimental and theoretical observation of a breaking point in the quasilinear relationship between the average collision cross sections and the number of monomer units for the triply charged cations. This breaking point was theoretically demonstrated, for the doubly and triply charged cations, to be associated with a significant folding of the polymer chains around the cationizing agents. The occurrence of such breaking points could be exploited to correlate the charge state of the most intense ion series observed upon electrospray ionization with the number-average molecular mass of a polymer.
authors: Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMONS, Mons, Belgium.
authors: Julien
authors: J
authors: De Winter
authors: Vincent
authors: V
authors: Lemaur
authors: Renaud
authors: R
authors: Ballivian
authors: Fabien
authors: F
authors: Chirot
authors: Olivier
authors: O
authors: Coulembier
authors: Rodolphe
authors: R
authors: Antoine
authors: Jérôme
authors: J
authors: Lemoine
authors: Jérôme
authors: J
authors: Cornil
authors: Philippe
authors: P
authors: Dubois
authors: Philippe
authors: P
authors: Dugourd
authors: Pascal
authors: P
authors: Gerbaux