A5040634905- Advanced NMR Techniques and Applications
- Atomic and Subatomic Physics Research
- Electron Spin Resonance Studies
- Gyrotron and Vacuum Electronics Research
- Superconducting Materials and Applications
- Solid-state spectroscopy and crystallography
- NMR spectroscopy and applications
- Particle accelerators and beam dynamics
- Physics of Superconductivity and Magnetism
- Muon and positron interactions and applications
- Advanced MRI Techniques and Applications
- Microwave and Dielectric Measurement Techniques
- DNA and Nucleic Acid Chemistry
- Quantum, superfluid, helium dynamics
- RNA Research and Splicing
- Superconductivity in MgB2 and Alloys
- X-ray Spectroscopy and Fluorescence Analysis
- Quantum and electron transport phenomena
- Scientific Research and Discoveries
- Nuclear and radioactivity studies
- Electron and X-Ray Spectroscopy Techniques
- Spacecraft and Cryogenic Technologies
- Advanced biosensing and bioanalysis techniques
- Fullerene Chemistry and Applications
- Ga2O3 and related materials
ETH Zurich
2019-2024
Washington University in St. Louis
2017-2023
University of Iceland
2020
Noguchi Memorial Institute for Medical Research
2020
University of Ghana
2020
Solid state nuclear magnetic resonance (NMR) enables atomic-resolution characterization of the molecular structure and dynamics within complex heterogeneous samples, but it is typically insensitive. Dynamic polarization (DNP) increases NMR signal intensity by orders magnitude can be performed in combination with magic angle spinning (MAS) for sensitive, high-resolution spectroscopy. Here we report MAS DNP experiments, first time, intact human cells >40-fold enhancement a sample temperature...
Dynamic nuclear polarization (DNP) can enhance NMR sensitivity by orders of magnitude transferring spin from electron paramagnetic resonance (EPR) to NMR. However, DNP polarizing agents have deleterious effects on signals. Electron decoupling mitigate these relaxation effects. We demonstrate experiments in conjunction with and magic-angle-spinning spectroscopy. Following a diffusion period, the microwave irradiation frequency is quickly tuned on-resonance electrons agent. The performance...
Spherical rotors can be used for magic angle spinning nuclear magnetic resonance.
Gallia-based shells with a thickness varying from submonolayer to ca. 2.5 nm were prepared by atomic layer deposition (ALD) using trimethylgallium, ozone, and partially dehydroxylated silica, followed calcination at 500 °C. Insight into the atomic-scale structure of these was obtained high-field 71Ga solid-state nuclear magnetic resonance (NMR) experiments modeling X-ray differential pair distribution function data, complemented Ga K-edge absorption spectroscopy 29Si dynamic polarization...
We demonstrate the construction of 7 Tesla and 12 all high-temperature-superconducting (HTS) magnets, small enough to fit on your wrist. The size magnet reduces cost fabrication, decreases fringe field permit facile siting stored energy high magnets. These HTS-based magnets are being developed for gyrotron microwave sources use in high-field nuclear magnetic resonance applications. employ a no-insulation winding technique cooled 4.2 Kelvin liquid helium cryostat. is single pancake coil, made...
Dynamic nuclear polarization (DNP) is used to improve the inherently poor sensitivity of magnetic resonance spectroscopy by transferring spin from electrons nuclei. However, DNP radicals within sample can have detrimental effects on spins close polarizing agent. Chirped microwave pulses and electron decoupling (eDEC) attenuate these in model systems, but this approach yet be applied intact cells or cellular lysates. Herein, we demonstrate for first time exceptionally fast 1H T1DNP times just...
The no-insulation (NI) high-temperature superconductor (HTS) winding technique enables the fabrication of highly compact magnets with self-quench protection. NI pancake coils are implemented to develop a 28-T HTS magnet for operation 792-GHz gyrotron, which is microwave source dynamic nuclear polarization magnetic resonance. To this end, three all-GdBCO double (DP) were fabricated using different diameters and procedures. objective was explore mechanical coil protection mechanisms at high...
Abstract We present a compact 23 T no-insulation (NI) magnet that was wound with 60 m of 10 mm wide high temperature superconducting (HTS) tape. The consists only one pocket-sized double pancake (DP) coil an inner diameter ∼6 mm, height 20 and outer 41.6 mm. Another NI similar size but larger 8 reached slightly lower magnetic field 21 T. also smaller which HTS tape still achieved 16 During the experiments in liquid helium, each charged to current between 690 A 850 A, corresponding density...
We demonstrate for the first time in-cell dynamic nuclear polarization (DNP) in conjunction with flow cytometry sorting to address cellular heterogeneity of samples. Utilizing a green fluorescent protein (GFP) reporter HIV reactivation, we correlate increased 15N resonance intensity cytokine-driven reactivation human cell line model latency. As few as 10% GFP+ cells could be detected by DNP magnetic (NMR). The inclusion cytometric prior analysis DNP-NMR further boosted signal detection...
Magic angle spinning (MAS) dynamic nuclear polarization (DNP) is widely used to increase magnetic resonance (NMR) signal intensity. Frequency-chirped microwaves yield superior control of electron spins and are expected play a central role in the development DNP MAS experiments. Time domain with has considerable promise improve performance at higher fields temperatures. We have recently demonstrated that pulsed decoupling using frequency-chirped improves experiments by partially attenuating...
A significant effort has recently been initiated at ETHZ for the development of high frequency, power, frequency-agile gyrotrons DNP-NMR spectroscopy. In this context an in house cavity interaction code is under development. paper, some details on new and preliminary results will be presented.
Abstract Dynamic nuclear polarization (DNP) increases NMR sensitivity by transferring from electron to spins. Herein, we demonstrate that decoupling with chirped microwave pulses enables improved observation of DNP‐enhanced 13 C spins in direct dipolar contact spins, thereby leading an optimal delay between transients largely governed relatively fast relaxation. We report the first measurement longitudinal relaxation time (T 1e ) during magic angle spinning (MAS) signals =40±6 ms, 40 m M...
Precise alignment of the sample's spinning axis is vital for many magic angle solid state NMR experiments. Spherical rotors are a new paradigm NMR, having been demonstrated to spin stably with little risk rotor crash, but like cylindrical rotors, they have previously only utilized mechanical adjustment method set rotation angle. Here we show that by using second gas aperture within stator, spherical rotor's may be precisely pitched about without or motion stator. The 2H MAS sideband...