title: Self-assembled trityl radical capsules--implications for dynamic nuclear polarization.
abstract: A new class of guest-induced, bi-radical self-assembled organic capsules is reported. They are formed by the inclusion of a tetramethylammonium (TMA) cation between two monomers of the stable trityl radical OX63. OX63 is extensively used in dissolution dynamic nuclear polarization (DNP) where it leads to NMR sensitivity enhancements of several orders of magnitude. The supramolecular properties of OX63 have a strong impact on its DNP properties. An especially relevant case is the polarization of choline-containing metabolites, where complex formation between choline and OX63 results in faster relaxation.
authors.affiliation: Biomolecular NMR laboratory, Department of Organic Chemistry, University of Barcelona, Cluster Building, Barcelona Science Park, Baldiri Reixac, 10-12, 08028 Barcelona, Spain. mpons@ub.edu.
authors.forename: I
authors.initials: I
authors.lastname: Marin-Montesinos
authors.forename: J C
authors.initials: JC
authors.lastname: Paniagua
authors.forename: M
authors.initials: M
authors.lastname: Vilaseca
authors.forename: A
authors.initials: A
authors.lastname: Urtizberea
authors.forename: F
authors.initials: F
authors.lastname: Luis
authors.forename: M
authors.initials: M
authors.lastname: Feliz
authors.forename: F
authors.initials: F
authors.lastname: Lin
authors.forename: S
authors.initials: S
authors.lastname: Van Doorslaer
authors.forename: M
authors.initials: M
authors.lastname: Pons
mesh_terms: D002214:Capsules / Q000737:chemistry*; D019281:Dimerization; D004578:Electron Spin Resonance Spectroscopy; D007192:Indenes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013696:Temperature; D014320:Triphenylmethyl Compounds / Q000737:chemistry*
chemical_list: D002214:Capsules; D007192:Indenes; C000602258:OX63 trityl radical; D000644:Quaternary Ammonium Compounds; D014320:Triphenylmethyl Compounds; C027917:tetramethylammonium