Session FOA. There are 5 abstracts in this session.



Session: MATERIALS 2, time: 8:30 - 8:45 am

Guiding the design of novel drug nanocarriers by MAS NMR.


Marianna Porcino1; Jingwen Qiu3; Lisa Xue3; Ioanna Christodoulou3; Mai D. L. Vuong2, 3; Ruxandra Gref3; Charlotte Martineau-Corcos1, 2
1CEMHTI UPR CNRS 3079, Orléans, france; 2Institut Lavoisier de Versailles (ILV), Versailles, France; 3ISMO UMR CNRS 8214, Orsay, France

The aim of drug delivery systems is to enable that a pharmaceutical compound successfully accomplishes its biological action. There is no universal drug nanocarriers, hence for each medical target, a new one must be designed. The ideal candidate has high colloidal stability, is prepared without toxic solvent, has high loading capacity, is non immunogenic, biodegradable and easy to fabricate. Furthermore, the interactions between the drug and the nanocarrier must be understood so that the drug release, delivery rate and fate of the degraded nanocarrier can be controlled. We show here how advanced liquid/solid-state NMR coupled to selective 13C-labeling allows addressing these challenging questions. The obtained information guides our search for more efficient engineered CD materials in the formulation of DDSs.


Session: MATERIALS 2, time: 8:45 - 9:00 am

Efficient detection of quadrupole nuclei using long pulses


Ivan Hung; Peter Gor'kov; Zhehong Gan
NHMFL, Tallahassee, FL
Long-pulse encoding and recoupling are used for efficient and sideband-free HMQC or CP experiments of quadrupole nuclei. For spin=3/2, detecting the double-quantum satellite-transition via TRAPDOR-HMQC enhances the spectral resolution by a factor up to 18 over the conventional central-transition spectra.

Session: MATERIALS 2, time: 9:00 - 9:15 am

Local Structure and Magnetism of LaxM1−xPO4 (M=RE, An, 0≤x≤1)


Laura Martel1; Ashraful Islam2; Karin Popa1; Aydar Rakhmatullin3; José J. Baldoví4; Mauro Perfetti5; Michael Deschamps3; Eric Colineau1; Attila Kovács1; Hélène Bolvin2; Jean-Christophe Griveau1
1JRC-Karlsruhe, Eggenstein Leopoldshafen, Germany; 2LCPQ-IRSAMC, Toulouse, France; 3CEMHTI, Orléans, France; 4University of Valencia, Valencia, Spain; 5Department of Chemistry, University of Copenhagen, Copenhagen, Denmark

Monazites are considered as potential matrices for encapsulation of nuclear wastes due to their high resistance to radiation damage. We will present a work done on a series of crystalline LaxM1−xPO4 (M=RE, An, 0≤x≤1). More specifically for this abstract, we give the example of the sample La0.9Eu0.1PO4. We probe its local structure using 31P MAS-NMR and perform magnetic susceptibility measurements. The curves are analysed using crystal field theory allowing to extract the electronic structure. We then propose an attribution of the NMR signals based on these calculations. Finally, the results will be compared with the one obtained for the actual actinide monazites.


Session: MATERIALS 2, time: 9:15 - 9:30 am

1000-fold Sensitivity Enhancement for Natural Abundance 17O NMR in Solids Achieved through Extended Coherence Lifetimes


Mark Bovee1; Daniel Jardón-Álvarez1; Jay Baltisberger2; Philip Grandinetti1
1Ohio State University, Columbus, OH; 2Berea College, Berea, KY

We show that the coherence lifetime of half-integer quadrupolar nuclei through a π pulse train can be extended by up to two orders of magnitude through highly selective excitation of the symmetric central (±1/2 → ∓1/2) transition. For instance, we measure an 17O T2 of 262 ± 1 s in α-quartz. These long coherence lifetimes translate into enormous sensitivity gains for echo train acquisition. By combining a satellite population transfer scheme, such as RAPT, with a low power (2.73 kHz) CPMG on 17O in α-quartz, we obtain over a 1000-fold sensitivity enhancement, i.e., million-fold decrease in acquisition time, compared to a spectrum obtained from a FID at a more commonly used power of 32.5 kHz.


Session: MATERIALS 2, time: 9:30 - 9:45 am

DNP surface- and subsurface-enhanced NMR spectroscopy of quadrupolar nuclei


hiroki Nagashima1; julien Trébosc2; yoshihiron Kon1; kazuhiko Sato1; olivier Lafon2; jean-paul Amoureux2
1AIST, Tsukuba, Japan; 2Lille University, Lille, France

We demonstrate that an adiabatic RINEPT sequence yields 2-fold more efficient 1H-27Al DNP transfers than existing methods for short distance transfers, and benefits from higher robustness to rf-field, CSA, offset and 1H-1H interactions. This RINEPT-ASR4 is much more efficient than PRESTO and CPMAS for transfers via small hetero-nuclear dipolar couplings, i.e. to remote or low-g nuclei. With respect to PRESTO, this novel method yields gains of 3.9 for 17O of Al-O-Al species in g-alumina and 5.5 for 95Mo of MoO3 supported on TiO2. These gains represent a time reduction of 15 and 30. We combine the RINEPT-ASR4 with SPAM-MQMAS-QCPMG to observe DNP high-resolution spectra of quadrupolar nuclei.