Article
Biochemistry & Molecular Biology
Marta Bonaccorsi, Tanguy Le Marchand, Guido Pintacuda
Summary: Magic-Angle Spinning Nuclear Magnetic Resonance (MAS NMR) is a rapidly developing technique that complements solution NMR, X-ray crystallography, and electron microscopy for the biophysical characterization of microcrystalline, poorly crystalline or disordered protein samples. MAS NMR is ideal for investigating both structures and dynamics, and has been increasingly applied in structural biology research in recent years to describe conformational dynamics in various systems.
CURRENT OPINION IN STRUCTURAL BIOLOGY
(2021)
Article
Chemistry, Analytical
Alan Wong
Summary: High-Resolution Magic-Angle Spinning (HRMAS) NMR spectroscopy is considered an essential technique in metabolomics for assessing the biochemical composition of tissue samples. HRMAS localized profiling shows promise for spatial resolution of metabolic profiles within the sampling tissues.
ANALYTICAL METHODS
(2023)
Review
Chemistry, Physical
Kai Xue, Riddhiman Sarkar, Zdenek Tosner, Bernd Reif
Summary: Proton detection in solid state NMR is continuously advancing, and current achievements include the necessity of deuteration for optimal spectral quality, the superiority of 13CH3 isotopomers for methyl groups at high MAS frequencies, and the sensitivity enhancement with increased static magnetic field.
PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY
(2022)
Article
Biochemical Research Methods
Evgeny Nimerovsky, Stefan Becker, Loren B. Andreas
Summary: In this study, we investigate the windowed sequence for cross polarization (wCP) and find that it has additional matching conditions compared to traditional cross polarization. By considering the flip angle of the pulse, we observe a striking similarity between wCP and CP transfer conditions. Using spin-1/2 formalism and average Hamiltonian theory, we derive an analytical approximation that matches these observed transfer conditions. Data recorded at spectrometers with different external magnetic fields show that these transfers and the selectivity of CP are related to flip angle (average nutation).
JOURNAL OF MAGNETIC RESONANCE
(2023)
Article
Chemistry, Physical
Debashis Majhi, Boris B. Kharkov, Sergey Dvinskikh
Summary: Dipolar NMR spectroscopy is a powerful analytical tool for studying structural and dynamic properties of solids at the molecular level. An approach to determine the signs of dipolar couplings in liquid crystals is presented, where sign information can be directly obtained from one-dimensional NMR spectra in samples spinning slightly off the magic angle. This method can be used to develop an experimental strategy for sign-sensitive measurements of heteronuclear dipolar couplings in anisotropic soft materials.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Biochemistry & Molecular Biology
Evgeny Nimerovsky, Kumar Tekwani Movellan, Xizhou Cecily Zhang, Marcel C. Forster, Eszter Najbauer, Kai Xue, Riza Dervisoglu, Karin Giller, Christian Griesinger, Stefan Becker, Loren B. Andreas
Summary: The available magnetic field strength for high resolution NMR in persistent superconducting magnets has recently improved, leading to increased proton resonance frequency and improved resolution for some membrane proteins in MAS NMR spectra.
Article
Biochemistry & Molecular Biology
Roman Zadorozhnyi, Sucharita Sarkar, Caitlin M. Quinn, Kaneil K. Zadrozny, Barbie K. Ganser-Pornillos, Owen Pornillos, Angela M. Gronenborn, Tatyana Polenova
Summary: Histidine residues in proteins play crucial structural and functional roles, such as metal-binding and enzyme catalysis. This study introduces a fast MAS NMR approach to determine the protonation and tautomeric states of His at frequencies of 40-62 kHz, using H-1 detection and TEDOR-based filters in 2D heteronuclear correlation experiments. The approach is demonstrated using microcrystalline assemblies of HIV-1 CA(CTD)-SP1 protein.
FRONTIERS IN MOLECULAR BIOSCIENCES
(2021)
Article
Biochemical Research Methods
Jose P. Carvalho, Wassilios Papawassiliou, Andrew J. Pell
Summary: This article presents a combination of solid-state NMR methods for extracting the 23Na shift and quadrupolar parameters in the structurally complex NaMnO2 Na-ion cathode material. By combining multiple experiments, the shift and quadrupolar parameters for observed Na environments were determined and showed agreement with theoretical models.
JOURNAL OF MAGNETIC RESONANCE
(2022)
Article
Chemistry, Multidisciplinary
Faezeh Nami, Maria Joao Ferraz, Thomas Bakkum, Johannes M. F. G. Aerts, Anjali Pandit
Summary: This study reports a method for tracking microbial fermentation, lipid metabolism, and structural dynamic changes using nuclear magnetic resonance (NMR) technology. The results show that lipolysis under dark and anoxia conditions leads to the breakdown of cell and organelle membranes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Physical
Bianca Chandler, Lauren Todd, Steven O. Smith
Summary: G protein-coupled receptors (GPCRs) are a class of transmembrane proteins with a simple structure that can recognize diverse chemical signals. There are over 800 GPCRs encoded in the human genome, serving as receptors for vision, smell, taste, and other physiological processes. While protein crystallography and electron cryo-microscopy have provided high-resolution structures of GPCRs, the structural changes induced by ligand or drug binding to stabilize active or inactive conformations are often subtle. NMR spectroscopy can provide insights into the local structure, dynamics, and activation pathways of GPCRs, capturing intermediate states and low-population conformations. Solid-state magic angle spinning NMR has been used to study the structure and activation mechanisms of GPCRs, particularly in the diverse class A family. This review highlights the application of solid-state and solution-state NMR spectroscopy in understanding the activation of different GPCR classes and subfamilies by their ligands and the modulation of GPCR activation by small molecule drugs. (c) 2021 Elsevier B.V. All rights reserved.
PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY
(2022)
Article
Engineering, Environmental
Guoqing Wang, Chen Chen, Bayu Admasu Beshiwork, Bo Xu, Yingchao Dong, Bin Lin
Summary: This study investigates the ionic conductivity and water transport properties of ceramic membrane-based magic-angle graphene. It reveals that the proton conduction and water transport in magic-angle graphene can be tuned by the twist angle, and the proton transport in magic-angle graphene is faster than that in graphene. The study also demonstrates the potential application of ceramic membrane-based magic-angle graphene in proton-conducting and water-transport materials for energy and environment.
Article
Biochemical Research Methods
Andrea Bertarello, Pierrick Berruyer, Urban Skantze, Samiksha Sardana, Malvika Sardana, Charles S. Elmore, Markus Schade, Elisabetta Chiarparin, Staffan Schantz, Lyndon Emsley
Summary: Dynamic nuclear polarization (DNP) significantly enhances the sensitivity of MAS NMR, but cross polarization (CP) is usually not quantitative. Research shows that absolute quantification in MAS DNP NMR is possible under DNP conditions, with errors below 10%.
JOURNAL OF MAGNETIC RESONANCE
(2021)
Article
Biochemical Research Methods
Yong Du, Derek Frank, Zhenxuan Chen, Jochem Struppe, Yongchao Su
Summary: Protons are the most NMR-sensitive nucleus in pharmaceutical compounds, and proton-detected solid-state NMR techniques under fast magic angle spinning are used to overcome low sensitivity challenges in analyzing natural abundant drug substances and products. This study reports the structural characterization of crystal polymorphs of a commercial drug molecule, posaconazole, using proton-detected homo- and heteronuclear correlation methods. The enhanced sensitivity and resolution enable the exploration of distinct intermolecular packing in posaconazole forms I, III, and c.
JOURNAL OF MAGNETIC RESONANCE
(2023)
Article
Chemistry, Physical
Vaishali Arunachalam, Kshama Sharma, Kaustubh R. Mote, P. K. Madhu
Summary: Recoupling, decoupling, and multidimensional correlation experiments in MAS solid-state NMR can be designed by exploiting the symmetry of internal spin interactions. This study demonstrates an asynchronous implementation of the C5(2)(1) sequence and its supercycled version SPC5(2)(1), which leads to higher double-quantum homonuclear polarization transfer efficiency compared to the normal synchronous implementation.
SOLID STATE NUCLEAR MAGNETIC RESONANCE
(2023)
Article
Biochemical Research Methods
Daniel Banks, Brian Michael, Natalie Golota, Robert G. Griffin
Summary: This paper discusses the use of 3D printing and rapid prototyping methods to fabricate 3.2 mm stators and drive caps for NMR experiments. With the assistance of CAD software, these components can be produced at a fraction of the cost of commercial parts, while demonstrating comparable performance to commercially available systems.
JOURNAL OF MAGNETIC RESONANCE
(2022)
Article
Chemistry, Inorganic & Nuclear
Takayuki Suehiro, Masataka Tansho, Toru Ishigaki, Tadashi Shimizu
Summary: The study investigated the ZnGeN2-GaN solid-solution system in previously unexplored compositional regions, revealing the transitional properties caused by the introduction of Ga. The results showed that increasing Ga content led to gradual red shifts in the absorption and photoluminescence properties of the samples.
INORGANIC CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Shenghan Gao, Thibault Broux, Susumu Fujii, Cedric Tassel, Kentaro Yamamoto, Yao Xiao, Itaru Oikawa, Hitoshi Takamura, Hiroki Ubukata, Yuki Watanabe, Kotaro Fujii, Masatomo Yashima, Akihide Kuwabara, Yoshiharu Uchimoto, Hiroshi Kageyama
Summary: Most solid-state materials are made up of p-block anions, but the introduction of hydride anions (1s(2)) in oxides has led to the discovery of interesting properties. By combining hydride anions with chalcogenide anions, a family of antiperovskites has been created with soft anionic sublattices. The M(3)HCh antiperovskites (M=Li, Na) exhibit ideal cubic structures, showing low migration barriers for Li+/Na+ transport and high ionic conductivity.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Tetsuo Umegaki, Haruka Ogawa, Kazuki Watanabe, Shinobu Ohki, Masataka Tansho, Tadashi Shimizu, Yoshiyuki Kojima
Summary: This study found that the dispersion of immobilized active molybdic acid depends on the amount of aqueous L-aspartic acid solutions added and the treatment of hollow sphere particles, with highly dispersed immobilized active molybdic acid showing higher catalytic activity for acid-promoted hydrolytic hydrogen generation from ammonia borane.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Review
Chemistry, Inorganic & Nuclear
Shinsuke Ishihara, Takeshi Machino, Kenzo Deguchi, Shinobu Ohki, Yuuki Mogami, Masataka Tansho, Tadashi Shimizu, Jonathan P. Hill, Yusuke Yamauchi, Nobuo Iyi
Summary: The study introduces a method to stably generate NO using nitrite ions in LDH, enabling NO inhalation therapy in developing countries and nonhospital settings. This inexpensive and disposable NO generator allows for mass production and provides a portable source for emergency situations, showcasing excellent controllability of solid-state reactions in LDH interlayer nanospace.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Takahiro Iijima, Shinobu Ohki, Masataka Tansho
Summary: The study presents a method to obtain separated pure-quadrupole and shift spectra of H-2 nuclear magnetic resonance of paramagnetic solids using simple pulse sequences, and applies affine transform operations to process signal data for obtaining the separated spectra. Further analysis of dynamics based on temperature dependence of the separated spectra was conducted for paramagnetic CoSiF6.6D2O system.
SOLID STATE NUCLEAR MAGNETIC RESONANCE
(2021)
Article
Chemistry, Physical
Hiroaki Kawamori, Itaru Oikawa, Hitoshi Takamura
Summary: This study achieved highly hydrated perovskite-type oxide through high-pressure synthesis, increasing proton concentration by utilizing Sc vacancies and excess protons. A novel mechanism to enhance proton concentration of perovskite-type proton conductors was revealed by compensating B-site charge with protons residing in Sc vacancies and extensive hydration conditions. The electrical conductivity at 450-500 degrees C was comparable to that of acceptor-doped BaZrO3, with a discontinuous change at dehydration temperature.
CHEMISTRY OF MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Mina Yamaguchi, Akihiro Ishii, Itaru Oikawa, Yusuke Yamazaki, Masaaki Imura, Hitoshi Takamura
Summary: Thin films of 60 mol % Ag-40 mol % (Fe1-xAlx)-O prepared by pulsed laser deposition exhibit promising optical properties, electrical resistance, and thermal stability, demonstrating their potential as black AR coatings.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Akihiro Ishii, Hibiki Ishijima, Kosei Kobayashi, Itaru Oikawa, Hitoshi Takamura
Summary: The key element for low-temperature sintering of Sm-doped CeO2 was found to be aluminum, which was spontaneously introduced through a chemical reaction with mixed lithium and alumina crucible. Zirconium was also introduced through ball-mill processing. Both aluminum and zirconium play an important role in reducing the melting point and achieving low-temperature sintering.
Article
Physics, Atomic, Molecular & Chemical
Takahiro Iijima, Takahiro Abe, Kenzo Deguchi, Shinobu Ohki, Masataka Tansho
Summary: Solid-state Pb-207 NMR spectroscopy was used to identify pigments on cultural heritage materials, determining Pb3O4 as the red pigment on a historical clay doll. Computational simulations showed inaccuracies with smaller PbOn fragments and the need for larger clusters to improve accuracy, even with fully relativistic methods.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Engineering, Multidisciplinary
Zaka Ruhma, Keiji Yashiro, Itaru Oikawa, Hitoshi Takamura, Tatsuya Kawada
Summary: This study focuses on the effects of pore former in metal slurry on the sintered layer of metal-supported SOFC, showing that changing the amount of pore former in the slurry can alter the sinterability of the metal layer and subsequently impact the final warpage state of the cell. The research helps in understanding the sintering phenomena between layers of metal-supported SOFCs.
JOURNAL OF ENGINEERING AND TECHNOLOGICAL SCIENCES
(2021)
Article
Chemistry, Multidisciplinary
Kenjiro Hash, Hideyuki Shinagawa, Shinobu Ohki, Yuuki Mogami, Teruaki Fujito, Tadashi Shimizu, Masataka Tansho, Atsushi Goto
Summary: A sample tube for solid-state NMR has been developed, allowing the application of high-intensity radiofrequency fields. By inserting an rf-shielding device into the tube and loading the sample between them, the flux of the rf-field is compressed into the sample space, resulting in a high-intensity rf-field at the sample. A prototype experiment showed that the rf-field strength at the sample can be increased up to twice that of a compared device.
Article
Chemistry, Multidisciplinary
Daichi Kato, Osamu Tomita, Ryky Nelson, Maria A. Kirsanova, Richard Dronskowski, Hajime Suzuki, Chengchao Zhong, Cedric Tassel, Kohdai Ishida, Yosuke Matsuzaki, Craig M. Brown, Koji Fujita, Kotaro Fujii, Masatomo Yashima, Yoji Kobayashi, Akinori Saeki, Itaru Oikawa, Hitoshi Takamura, Ryu Abe, Hiroshi Kageyama, Tatiana E. Gorelik, Artem M. Abakumov
Summary: Layered bismuth oxyhalides with bilayered (Bi2O2) fluorite slabs are promising visible-light photocatalysts due to their excellent stability and the ability to adjust band levels. Manipulating the Bi2O2 slab allows control over the structure and properties, creating new research opportunities.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Masataka Tansho, Atsushi Goto, Shinobu Ohki, Yuuki Mogami, Yuichi Sakuda, Yuta Yasui, Taito Murakami, Kotaro Fujii, Takahiro Iijima, Masatomo Yashima
Summary: This study investigated the coordination structures of Mo and Nb in the high-oxide-ion conductor Ba3MoNbO8.5 using solid-state nuclear magnetic resonance (NMR) measurements. The results suggest that MoO5 polyhedra may play an important role in ionic conduction.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Energy & Fuels
Tetsuo Umegaki, Haruka Ogawa, Kazuki Watanabe, Shinobu Ohki, Masataka Tansho, Tadashi Shimizu, Yoshiyuki Kojima
Summary: In this study, the influence of the pore structure of molybdic acid-immobilized silica-alumina hollow spheres on their activity towards acid-promoted hydrogen evolution from aqueous ammonia borane solution was investigated. The amount of surfactant and swelling agent used during the shell formation of the hollow spheres was found to affect the amount of mesopores formed. Additionally, the crystallinity of the immobilized molybdic oxide species and the ratio of inactive mixed oxides of aluminum and molybdenum decreased with increasing amounts of the surfactant and swelling agent. The immobilized hollow spheres with high dispersed molybdic oxide and high inactive mixed oxide ratio exhibited high activity towards hydrogen evolution from aqueous ammonia borane solution, while low molybdic oxide content in the hollow spheres also resulted in high activity.
JOURNAL OF THE JAPAN INSTITUTE OF ENERGY
(2022)
Article
Chemistry, Physical
Hiroki Uehara, Akihiro Ishii, Itaru Oikawa, Hitoshi Takamura
Summary: A new mixed proton-hole conducting material is developed by doping cobalt into BaZr1-xScxO3-delta, which exhibits high hole conductivity. The study investigates the phases present, proton incorporation, and electrical conductivity of BaCoxZr0.9-xSc0.1O3-delta. It is found that Sc doping increases the cobalt solubility limit in BaZrO3 and conductive protons are incorporated in the bulk portion of Co, Sc-doped BaZrO3. BaCoxZr0.9Sc0.1O3-delta shows higher conductivity than Fe or Pr doped BaMxZr1-x-yYyO3-delta. The maximum conductivity is achieved for BaCo0.2Zr0.7Sc0.1O3-delta in both wet and dry oxidizing atmospheres.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
