High-pressure Nuclear Magnetic Resonance Spectroscopy Research Articles

Disentangling the Li-Ion transport and Boundary Phase Transition Processes in Li10 GeP2 S12 Electrolyte by In-Operando High-Pressure and High-Resolution NMR Spectroscopy.

Li-ion transport and phase transition of solid electrolytes are critical and fundamental issues governing the rate and cycling performances of solid-state batteries. In this work, in-operando high-pressure nuclear magnetic resonance (NMR) spectroscopy for the solid-state battery is developed and applied, in combination with 6 Li-tracer NMR and high-resolution NMR spectroscopy, to investigate the Li10 GeP2 S12 electrolyte under true-to-life operation conditions. The results reveal that the Li10 GeP2 S12 phase may become more disordered and a large amount of conductive metastable β-Li3 PS4 as the glassy matrix in the electrolyte transforms into less conductive phases, mainly γ-Li3 PS4 , when high current densities (e.g., ≥0.5mA cm-2 ) are applied to the electrolyte. The overall Li-transport also varies and shows a tendency of boundary phases and Li10 GeP2 S12 synergistic dominant conduction at high currents. Accordingly, a mechanism of structural change induced by stress variation due to the drastic morphological change during Li-In alloying at high currents, and the local Li+ diffusion coefficient discrepancy is proposed. These new findings of Li-ion transport and boundary phase transition in Li10 GeP2 S12 solid electrolyte under high-pressure and high current density are first reported and will help provide previously lacking insights into the relationship of structure and performance of Li10 GeP2 S12 .

Boron needle stitches carbon thread

Organic Chemistry The Fischer-Tropsch process relies on transition metal catalysis at high temperature to stitch together carbon monoxide and hydrogen into hydrocarbon chains. Phanopoulos et al. now report that a pair of boron reagents can do something similar at room temperature, albeit less efficiently. Specifically, the combination of a terminal alkyl borane and triethylborohydride can catenate as many as eight carbon monoxide equivalents, producing a mixture of linear aldehydes after oxidative workup. Theoretical simulations and high-pressure nuclear magnetic resonance spectroscopy elucidated the catalytic role of the terminal boron center. J. Am. Chem. Soc. 142 , 14064 (2020).

A reactor for high-throughput high-pressure nuclear magnetic resonance spectroscopy.

The design of a reactor for operando nuclear magnetic resonance (NMR) monitoring of high-pressure gas-liquid reactions is described. The Wisconsin High Pressure NMR Reactor (WiHP-NMRR) design comprises four modules: a sapphire NMR tube with titanium tube holder rated for pressures as high as 1000 psig (68 atm) and temperatures ranging from -90 to 90 °C, a gas circulation system that maintains equilibrium concentrations of dissolved gases during gas-consuming or gas-releasing reactions, a liquid injection apparatus that is capable of adding measured amounts of solutions to the reactor under high pressure conditions, and a rapid wash system that enables the reactor to be cleaned without removal from the NMR instrument. The WiHP-NMRR is compatible with commercial 10 mm NMR probes. Reactions performed in the WiHP-NMRR yield high quality, information-rich, and multinuclear NMR data over the entire reaction time course with rapid experimental turnaround.

High-Pressure NMR Spectroscopy Reveals Functional Sub-states of Ubiquitin and Ubiquitin-Like Proteins.

High-pressure nuclear magnetic resonance (NMR) spectroscopy has revealed that ubiquitin has at least two high-energy states--an alternatively folded state N2 and a locally disordered state I--between the basic folded state N1 and totally unfolded U state. The high-energy states are conserved among ubiquitin-like post-translational modifiers, ubiquitin, NEDD8, and SUMO-2, showing the E1-E2-E3 cascade reaction. It is quite intriguing that structurally similar high-energy states are evolutionally conserved in the ubiquitin-like modifiers, and the thermodynamic stabilities vary among the proteins. To investigate atomic details of the high-energy states, a Q41N mutant of ubiquitin was created as a structural model of N2, which is 71% populated even at atmospheric pressure. The convergent structure of the "pure" N2 state was obtained by nuclear Overhauser effect (NOE)-based structural analysis of the Q41N mutant at 2.5 kbar, where the N2 state is 97% populated. The N2 state of ubiquitin is closely similar to the conformation of the protein bound to the ubiquitin-activating enzyme E1. The recognition of E1 by ubiquitin is best explained by conformational selection rather than by induced-fit motion.

Pressure and protein dynamism

The dynamism of life depends critically on the dynamism of bio-macromolecules themselves, notably proteins. The bio-macromolecular dynamism originates from weak non-bonding interactions, which inevitably fluctuate under physiological conditions. The fascination lies in the fact that, in proteins, the basically random “non-biological fluctuations” of atoms are often turned into specific “biological fluctuations” of larger amplitude, which would be directly coupled to protein function and consequently the dynamism of life such as growth, motility, sensing, adaptation and disease. The success of the combination of pressure perturbation with advanced nuclear magnetic resonance (NMR) spectroscopy by using the online cell method has provided a powerful means for investigating details of such “biological fluctuations”, which encompass, in general, a much wider conformational space of a protein than hitherto explored. Some representative strategies of high pressure NMR spectroscopy for characterizing protein dynamism will be discussed with actual examples.

High pressure magnetic resonance imaging with metallic vessels

High pressure measurements in most scientific fields rely on metal vessels given the superior tensile strength of metals. We introduce high pressure magnetic resonance imaging (MRI) measurements with metallic vessels. The developed MRI compatible metallic pressure vessel concept is very general in application. Macroscopic physical systems are now amenable to spatially resolved nuclear magnetic resonance (NMR) study at variable pressure and temperature. Metallic pressure vessels not only provide inherently high tensile strengths and efficient temperature control, they also permit optimization of the MRI RF probe sensitivity. An MRI compatible pressure vessel is demonstrated with a rock core holder fabricated using non-magnetic stainless steel. Water flooding through a porous rock under pressure is shown as an example of its applications. High pressure NMR spectroscopy plays an indispensable role in several science fields. This work will open new vistas of study for high pressure material science MRI and MR.

Clinical and Epidemiological Metabonomics

Metabonomics is an omics approach to identify and monitor metabolic characteristics, changes, and phenotypes with respect to various synergetic factors such as environment, life style, diet, and potential pathophysiological processes. Recently, metabonomics has also opened up a possibility for functional genomics in large genome-wide studies. Mass spectrometry (MS) and proton nuclear magnetic resonance (NMR) spectroscopy are the two key experimental technologies in the field. Recent advancements are numerous, and methodologies currently exist that allow for automated high-throughput experimentation in a very cost-effective manner. Technical developments have evoked an increasing number of metabonomics applications in clinical and epidemiological disciplines to understand the complex molecular foundations of various diseases. Techniques with the aim of assessing large numbers of metabolites that are substrates, intermediates, or products in various metabolic pathways are particularly relevant in the risk assessment of metabolic conditions like diabetes and vascular diseases. It has also been envisioned that metabonomics approaches may overtake standard analytical measurements of individual metabolites and eventually lead to holistic multimetabolic risk phenotyping in the early detection of high-risk individuals for various metabolic diseases. Thus, metabonomics offers potential means to move away from single biomarkers and thresholds in clinical medicine. And, furthermore, even though the current medical biomarkers and thresholds are necessary benchmarks for clinical practice, it will be crucial to let the future diagnostics to follow from new science. Good predictions are necessary for effective prevention; an important step towards this is expected to happen when complex traits will not anymore be limited by clinical diagnoses and definitions but will be handled as multivariate continuous dimensions. Consequently, clinical and epidemiological metabonomics is likely to be one of the key new omics areas to assist translational research in the near future. Here, the Journal of Biomedicine and Biotechnology presents this special issue, 2011. Although only representing a small fraction of the contribution of metabonomics to various biomedical disciplines, the papers presented here show the increasing potential of metabonomics approaches to complement clinical and epidemiological research. To start the special issue, we have five contributions that review several aspects of metabonomics research. M. G. Barderas et al. discuss the concepts of metabolic profiling, fingerprinting, and footprinting focusing on the area of cardiovascular diseases. E. Silvestri and coworkers discuss the timely and relevant issue of integrative analyses of related omics data sets in order to furnish new insights not accessible through one-dimensional data. Further, I. Kouskoumvekaki and G. Panagiotou give an extensive up-to-date overview on the database resources on metabolic pathways and metabolomes and also summarize the statistical tools often used for the analysis of metabonomics data. Y. Kim and S. Milner deal with the challenges related to bioactive food components in cancer research and prevention. Moreover, M. Sofia and coauthors review the potential use of exhaled breath condensate as a suitable matrix for NMR-based metabonomics of airway diseases. This special issue contains two methodology reports. G. Kastenmuller and coworkers have developed a freely accessible methodology to facilitate automated and standardized analysis for quantitative metabolic data, covering the steps from data acquisition to biological interpretation. M. C. Martinez-Bisbal and colleagues, using magnetic resonance microscopy, present a critical and valuable interpretation on the high-resolution magic angle spinning data of human tumor tissues. The six original research papers in this special issue start with the paper by J. Willmann et al. who demonstrate the advantage of combining high-pressure liquid chromatography, MS, and NMR spectroscopy in analyzing three different types of extracts of a common membrane component phosphatidylcholine. Then, D. F. Brougham et al. focus on the use of artificial neural networks in classifying proton NMR spectroscopic data recorded on whole-cell culture samples of four different lung carcinoma cell lines, displaying different drug-resistance patterns. In a mouse study, D. Otter et al. apply MS-based nontargeted urinary metabolite profiling to identify biomarkers of colon inflammation. In another mouse study, J. Zhou et al. provide evidence that NMR metabonomics may be sensitive enough to detect small differences in the composition of maternal plasma and thus be helpful for identifying biomarkers of birth defects. Additionally, in low-birth weight and high-birth weight piglets P. M. Nissen and coworkers combine NMR and MS to reveal a relationship between birth weight and plasma inositols, suggesting their potential role in fetal programming of type 2 diabetes. L. Guo et al. end this special issue in providing the latest epidemiologic information on the etiology distribution of neurodevelopmental disabilities in Chinese, and by demonstrating, on the basis of 8-year clinical experience, that MS-based pediatric metabonomics is clinically helpful. Overall, we hope that this special issue hints at the rising potential of metabonomics approaches in clinical and epidemiological research and translational medicine. Mika Ala-Korpela Veikko Salomaa Olav M. Kvalheim

High-pressure autoclave for multipurpose nuclear magnetic resonance measurements up to 10 MPa

High-pressure nuclear magnetic resonance (NMR) is an established method in NMR spectroscopy: on-line coupling of high-performance liquid chromatography with NMR, for example, reveals structural information which cannot be obtained with any other method. However, applications has been focused solely on high-pressure NMR spectroscopy, even though high-pressure NMR imaging allows in situ studies of processes such as the fluid exchange in porous media. A versatile high-pressure autoclave for NMR imaging is described in this article. The autoclave allows measurements in any horizontal NMR imager using magnetic field coil systems with an inside diameter of more than 70 mm. Any sample with a diameter up to 28 mm and a length of about 200 mm can be investigated. The autoclave is constructed for operating pressures up to 10 MPa and is temperature controlled between 10 and 60 °C. The materials of the high-pressure cell which are the thermoplastic polyetheretherketon (PEEK) for the pressure tube and brass (63% Cu, 37% Zn) for the caps also permit investigations with aggressive fluids such as supercritical carbon dioxide. Inlet and outlet valves allow replacement of fluids and pressure variations in the autoclave during the NMR measurement. FLASH NMR images of the fluid exchange of methanol for liquid carbon dioxide in silica alcogels at 6.5 MPa are presented in order to demonstrate possible applications.

Enzymatic synthesis and chromatographic purification of lignan glucuronides.

Enterolactone, enterodiol and secoisolariciresinol were conjugated with glucuronic acid by solubilized rabbit liver microsomal UDP-glucuronyltrasnferase. The monoglucuronide conjugate of all three substrates was formed and its identity confirmed by nuclear magnetic resonance (NMR) spectroscopy. Analytical high pressure liquid chromatography (HPLC) and NMR spectroscopy indicated conjugation with glucuronic acid to occur at several positions in the molecule. The enzymatic conjugation was monitored by analytical capillary isotachophoresis (ITP). The Km-values for enterlactone, enterodiol, and secoisolariciresinol were calculated to be 0.30, 0.23, and 0.22 mmol/l respectively.