A5058726462- Advanced NMR Techniques and Applications
- Medical Imaging Techniques and Applications
- Solid-state spectroscopy and crystallography
- Advanced MRI Techniques and Applications
- Radiopharmaceutical Chemistry and Applications
- Muon and positron interactions and applications
- Electron Spin Resonance Studies
- Inorganic Fluorides and Related Compounds
- Molecular Spectroscopy and Structure
- NMR spectroscopy and applications
- Advanced X-ray and CT Imaging
- Quantum, superfluid, helium dynamics
- Radiation Dose and Imaging
- Medical Imaging and Pathology Studies
- Atomic and Subatomic Physics Research
- Fluorine in Organic Chemistry
- Atmospheric Ozone and Climate
- X-ray Diffraction in Crystallography
- Neuroscience and Neuropharmacology Research
- Cancer, Hypoxia, and Metabolism
- Spectroscopy and Laser Applications
- Cardiac Imaging and Diagnostics
- Monoclonal and Polyclonal Antibodies Research
- HER2/EGFR in Cancer Research
- Advanced Chemical Physics Studies
Queen Mary University of London
2015-2021
Invicro (United Kingdom)
2017-2020
General Electric (Spain)
2008-2018
Freie Universität Berlin
1999-2013
Kiel University
1999-2010
Laboratoire de Physique des Lasers, Atomes et Molécules
2009
Czech Academy of Sciences, J. Heyrovský Institute of Physical Chemistry
2009
Université de Lille
2009
Centre National de la Recherche Scientifique
2009
Physikalisch-Technische Bundesanstalt
2005
18F labeling strategies for unmodified peptides with [18F]fluoride require 18F-labeled prosthetics bioconjugation more often cysteine thiols or lysine amines. Here we explore selective radical chemistry to target aromatic residues applying C–H 18F-trifluoromethylation. We report a one-step route [18F]CF3SO2NH4 from and its application direct [18F]CF3 incorporation at tryptophan tyrosine using as complex recombinant human insulin. The fully automated radiosynthesis of...
To assess image quality in abdominal CT at low tube voltage combined with two types of iterative reconstruction (IR) four reduced contrast agent dose levels. Minipigs were scanned standard 320 mg I/mL concentration 120 kVp, and formulations 120, 170, 220 270 80 kVp IR. Image was assessed by value, normalized signal to noise ratio (CNRD SNRD) the arterial venous phases. Qualitative analysis included expert reading. Protocols 170 or higher showed equal superior values: aorta (278–468 HU versus...
The objective of this study is to investigate if trityl biradicals could lead more efficient dynamic nuclear polarization (DNP) for low gamma spins at temperature (≈1 K) than a monoradical. Three novel different size are synthesized, characterized and employed hyperpolarization [1-13C]pyruvic acid 3.35 T 4.64 T. Intramolecular electron–electron distances obtained via dipolar couplings from electron paramagnetic resonance (EPR) spectroscopy X-band W-band that match well with calculated...
In ultralow magnetic fields, liquid state nuclear resonance (NMR) spectra of homonuclear spin systems exhibit line widths dominated by their natural lifetime. Chemical shifts become negligible, and heteronuclear NMR show predominantly the electron-mediated field-independent J-coupling. However, weak polarization Larmor frequencies down to a few hertz require special detectors, such as Superconducting Quantum Interference Devices (SQUID), that also enable simultaneous detection broad band...
Locoregional recurrence of breast cancer poses significant clinical problems because frequent inoperability once the chest wall is involved. Early detection by molecular imaging agents against therapeutically targetable receptors, such as c-Met, would be potential benefit. The aim this study was to assess <sup>18</sup>F-AH113804, a peptide-based agent with high affinity for human early-stage locoregional in basal-like model, HCC1954. <b>Methods:</b> HCC1954 tumor–bearing xenograft models...
A selectively D2 labeled transition metal dihydride, Os(D2)(Cl)2(CO)(PiPr3)2, was synthesized and studied by 2H magic angle spinning (MAS) NMR spectroscopy. It found that the interference between quadrupolar homonuclear dipolar interaction results in a characteristic lineshape of MAS sidebands. The basic properties coupling on were elucidated, using average Hamiltonian theory, exact simulations experiments achieved stepwise integration equation motion density matrix. These show it is...
NMR crystallography, the combination of solid-state techniques, chemical modelling, quantum calculations and other characterization allows determination molecular supramolecular structures which are not amenable to standard X-ray crystallography. The method is demonstrated on a set application examples. First principles practical considerations crystallography based dipolar spectroscopy outlined in conformational studies polymorphs N-octyl-gluconamide methoxycarbonyl urea. Then structural...
Abstract The molecular configuration and intermolecular arrangement of polycrystalline methoxycarbonylurea (MCU) has been studied by a combination chemical editing, rotational echo double resonance (REDOR) spectroscopy ab initio calculations. From the multispin IS n REDOR experiments several dipolar couplings were determined converted into distance constraints. Intra‐ distinguished isotope dilution. MCU molecule can be from three torsion angles Ψ 1 , 2 3 . Ab calculations showed that these...
Objectives. To assess the impact of combining low-tube voltage acquisition with iterative reconstruction (IR) techniques on iodine dose in coronary CTA. Methods. Three minipigs underwent CCTA to compare a standard care protocol two alternative study protocols and low IR. Image quality was evaluated objectively by CT value, signal-to-noise ratio (SNR), contrast-to-noise (CNR) main arteries aorta subjectively expert reading. Statistics were performed Mann–Whitney <mml:math...
Magnetic dipolar couplings between the 15N atom (labeled) and neighboring 13C atoms (natural abundance) in three solid modifications of N-octyl-D-gluconamide are measured with rotational echo double resonance (REDOR). A unique spectral assignment resonances is possible by means their dephasing. While monolayer crystal fiber modification amenable to solution spectra, bilayer crystallites a different found. The range 45 1220 Hz converted into CN distances. These distances employed conjunction...
Abstract Low-temperature (193 K) 1 H, 13 C and 15 N NMR spectra of blue- red-shifting H-bonded complexes formed by fluoroform with various proton acceptors were measured. Experimental parameters plotted versus the ab initio calculated H-bond strength (MP2/6–31+G(d, p); interaction energy varies from ~5 up to 25 kJ · mol −1 in series). We show that experimental H shieldings, as well H/D isotope effect on shielding change monotonously strengthening. The chemical shift CH scalar coupling...
The study objective is to investigate the impact of a wide range contrast media (CM) iodine concentrations on CT enhancement at constant total dose (TID) and delivery rate (IDR). Seven injection protocols, based different ranging from 120 370 mg I/mL, were assessed 4 minipigs TID 320 I/kg IDR 0.64 g I/s. Dynamic images acquired clinical 64-slice MDCT scanner for s with abdominal aorta, vena cava inferior liver parenchyma in field-of-view. Maximal enhancement, time-to-peak peak width...
Abstract Methoxycarbonyl urea (MCU), a potential long-term nitrogen fertilizer, is studied by 13 C and 15 N dipolar chemical shift NMR spectroscopy ab initio calculations. Employing combination of NMR, selective isotope labeling gas phase calculations, possible molecular structures shielding tensors all nuclei two out the three were revealed. Four stable configurations molecule with different energies found in The CSA calculated for these configurations. While C(urea) tensor orientation...
Autoradiography potentially offers high molecular sensitivity and spatial resolution for tumor margin estimation. However, conventional autoradiography requires sectioning the sample which is destructive labor-intensive. Here we describe a novel technique that uses flexible ultra-thin scintillator conforms to surface. Imaging with enables direct, high-resolution high-sensitivity imaging of beta particle emissions from targeted radiotracers. The has potential identify positive margins in...
The molecular configuration and crystal structure of solid polycrystalline N,N''-diacetylbiuret (DAB), a potential nitrogen-rich fertilizer, have been analyzed by combination solid- liquid-state NMR spectroscopy, X-ray diffraction, DFT calculations. Initially pure study ("NMR crystallography") was performed as available single crystals DAB were not suitable for diffraction. Solid-state 13C spectra revealed the unexpected existence two polymorphic modifications (alpha- beta-DAB) obtained from...
A fully 13C–15N-labeled and a selectively alanine-13Cβ tryptophan-15Nring-labeled sample of the Src homology region 3 (SH3) domain α-spectrin (chicken), 62 residue protein, were biosynthesized studied by solid-state cross-polarization magic angle spinning (CP/MAS) NMR, 13C–15N rotational echo double resonance (REDOR) 15N–13C transferred (TEDOR) spectroscopy. In first part study it is shown that spectral editing with TEDOR sequence leads to drastic simplification 13C MAS spectrum labeled...