Interfaces Involving Biomolecules and Inorganic Materials: a Solid State NMR Approach
- PDF / 1,194,613 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 1 Downloads / 184 Views
1008-T02-09
Interfaces Involving Biomolecules and Inorganic Materials: a Solid State NMR Approach Christian Bonhomme1, Geoffrey Hartmeyer1, Florence Babonneau1, Michel Wong Chi Man2, Guilhem Arrachart2, Carole Carcel2, Joel Moreau2, and Bruno Alonso3 1 Laboratoire chimie de la matiËre condensÈe, Universite P et M Curie, 4 place Jussieu, Paris, France 2 Heterochimie moleculaire et supramoleculaire, ENSCM, Montpellier, 34296, France 3 UMR 5223 MACS, ENSCM, Montpellier, 34296, France
ABSTRACT Materials based on ureidopyrimidinone (UPY) dimers and Adenine (A) / Thymine (T) derivatives were synthesized and characterized by advanced solid state NMR (Nuclear Magnetic Resonance) techniques. Silylated UPY molecules were used as model compounds, leading to structured organic-inorganic materials after hydrolysis and condensation processes (sol-gel reactions). High resolution 1H solid state NMR has been extensively used for the in-depth description of the H-bond networks, including very fast MAS (Magic Angle Spinning) experiments at very high field and DQ (double quantum) recoupling experiments. The chemical nature of the organic-inorganic interface has been illuminated by such techniques. In, particular, it has been demonstrated that H-bond networks were preserved during sol-gel reactions and were comparable to those observed in the UPY crystalline precursors.
INTRODUCTION The synthesis of structured hybrid and bioinspired materials is crucial. It is mainly based on molecular assemblies including organic or biological molecules [1]. Generally, H-bonding plays a prominent role in bridging organic entities. The inorganic component is based mainly on silica derivatives obtained by sol-gel hydrolysis and condensation reactions. Obviously, the properties of the obtained materials are strongly related to the interface between the organic and inorganic components. As a matter of fact, the interface remains difficult to characterize from a spectroscopic point of view and solid state NMR appears as a valuable tool of investigation. 1 H is a key nucleus for the in-depth characterization of both the organic and inorganic components of a given material, including H-bond networks. High resolution 1H solid state NMR remains a theoretical and experimental challenge, as the homogeneous 1H-1H dipolar interaction is hardly averaged by standard techniques, such as MAS. Recent developments including fast MAS (up to 35 kHz), very high field (B0 = 17.6 T) and double quantum (DQ) excitation schemes [2] allowed for increase dramatically the resolution of proton spectra and to establish spatial connectivities between nuclei. The various chemical environments are characterized by the isotropic chemical shifts (δiso.(1H)), whereas the homonuclear dipolar interaction is sensitive to the internuclear distances. In this paper, hybrid materials based on silylated ureidopyrimidinone (Si-UPY) molecules were synthesized [3]. UPY molecules were often used within the frame of
supramolecular assemblies [4]. Such molecules are able to establish dimers involvi
Data Loading...
