title: Influence of Equilibration Time in Solution on the Inclusion/Exclusion Topology Ratio of Host-Guest Complexes Probed by Ion Mobility and Collision-Induced Dissociation.
abstract: Host-guest complexes are formed by the creation of multiple noncovalent bonds between a large molecule (the host) and smaller molecule(s) or ion(s) (the guest(s)). Ion-mobility separation coupled with mass spectrometry nowadays represents an ideal tool to assess whether the host-guest complexes, when transferred to the gas phase upon electrospray ionization, possess an exclusion or inclusion nature. Nevertheless, the influence of the solution conditions on the nature of the observed gas-phase ions is often not considered. In the specific case of inclusion complexes, kinetic considerations must be taken into account beside thermodynamics; the guest ingression within the host cavity can be characterized by slow kinetics, which makes the complexation reaction kinetically driven on the timescale of the experiment. This is particularly the case for the cucurbituril family of macrocyclic host molecules. Herein, we selected para-phenylenediamine and cucurbit[6]uril as a model system to demonstrate, by means of ion mobility and collision-induced dissociation measurements, that the inclusion/exclusion topology ratio varies as a function of the equilibration time in solution prior to the electrospray process.
authors.affiliation: Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.|Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.|Mass spectrometry Laboratory, University of Liège, 4000, Liège, Belgium.
authors.forename: Glenn
authors.initials: G
authors.lastname: Carroy
authors.affiliation: Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.|Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Daxhelet
authors.affiliation: Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Lemaur
authors.affiliation: Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.
authors.forename: Julien
authors.initials: J
authors.lastname: De Winter
authors.affiliation: Mass spectrometry Laboratory, University of Liège, 4000, Liège, Belgium.
authors.forename: Edwin
authors.initials: E
authors.lastname: De Pauw
authors.affiliation: Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Cornil
authors.affiliation: Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry, Research Institute for Science and Engineering of Materials, University of Mons - UMONS, 23 Place du Parc, 7000, Mons, Belgium. pascal.gerbaux@umons.ac.be.
authors.forename: Pascal
authors.initials: P
authors.lastname: Gerbaux
keywords: collision-induced dissociation; cucurbituril; density functional calculations; host-guest chemistry; ion mobility