NMR spectroscopy is known not only for its outstanding analytical power but also for the large size and costs of the instruments. In recent years, this family of instruments with bulky superconducting magnets has been complemented with compact tabletop and portable devices suitable for small-molecule analysis and nondestructive materials testing. The state-of-the-art of compact NMR instruments is reviewed and illustrated with selected examples.

Solid-state NMR provides unique information on the peculiarities of methane activation on zeolite catalysts. This allowed to discover the possibilities of methane transformation to methanol and other oxygenates as well as to rationalize co-conversion of methane with higher alkanes under mild conditions on Zn-modified zeolites.

Metabolomics is the omic science that best represents the molecular phenotype. Among several applications it has the potential to be translated into the clinical practice. This Review presents the NMR-vision of metabolomics, highlighting the high degree of standardization needed along the entire workflow (pre-analytics, NMR spectra acquisition and processing, statistical analysis and data deposition) for reliable and reproducible results.

Nuclear hyperpolarization is a powerful method that can dramatically enhance the sensitivity of NMR spectroscopy. This technology has been applied to the biomedical molecular imaging of a range of small molecules with stable isotopes and has provided valuable metabolic and physiological information. This review focuses on strategies for the design of molecular probes for hyperpolarized bioimaging.

The use of hyperpolarized ¹²⁹Xe has the potential to revolutionize clinical imaging, offering a non-ionizing contrast of organ function complementary to that of CT imaging and conventional MRI. In this Review, the physics of spin-exchange optical pumping (SEOP) is discussed, production modalities of hyperpolarized ¹²⁹Xe are explained, and biomedical applications to lung imaging and beyond are described.

CH–π interactions are crucial determinants for the affinity of arguably every drug molecule. PI by NMR can differentiate the strength of protein–ligand CH–π interactions in solution. By combining selective amino-acid side-chain labeling with ¹H-¹³C NMR, CH–π interactions can be identified based solely on ¹H chemical shift values. This information serves as a proxy for the strength of each individual CH–π interaction.

A graphical software package to analyse NMR titration and ITC experiments is presented. A brief introduction to the underlying mathematical and statistical aspects is given first. It is then followed by the demonstration of nonlinear fitting of models to example data and the application of statistical approaches like Monte Carlo simulation and F-test approaches to model functions, NMR titration data and results of ITC experiments.

DREAMTIME NMR overcomes spectral overlap and increases sensitivity, opening a new world for targeted NMR detection. A user can define any unique suite of compounds and isolate them without complex sample preparation. DREAMTIME can be directly joined to any existing NMR experiment (1D, nD or MRI) and holds promise for all areas of science from chemical engineering, through environmental monitoring, to medical diagnosis.

We describe a protein-selective labelling approach that allowed us to probe a single lipoprotein (BamC) in the pentameric BAM membrane protein complex by proton-detected solid-state NMR. Our results generate novel insights into the supramolecular structure of the BAM complex and provide evidence that the three BamC domains exhibit different dynamic properties within the 200 kDa complex embedded in lipid bilayers.

Low field Pulsed Field Gradient (PFG) NMR is demonstrated as an effective tool for measuring the tortuosity of catalyst materials containing paramagnetic species, which are unmeasurable at high magnetic field strengths. The technique is applied to catalyst precursors with industrially relevant metal loadings (up to 20 wt.%) and allows a direct measurement of tortuosity

Multiple noncovalent interactions involving cyclopentenyl cations in the methanol-to-olefins (MTO) reaction over ZSM-5 zeolite were identified by using two-dimensional solid-state NMR spectroscopy. It was found that the hydrocarbon pool reaction is modulated by carbocation-induced noncovalent interactions.

We report the liquid-sate NMR spectroscopy analysis of the dimeric SARS-CoV-2 main protease (3CLp), including its backbone assignments, to study its complex conformational regulation. Using fragment-based NMR screening, we highlighted three hotspots on the protein, two in the substrate binding pocket and one at the dimer interface, and we identified a non-covalent reversible inhibitor of 3CLp that has antiviral activity in infected cells.

The membrane orientation of the hepatitis C virus NS5A protein was assessed by combining a cell-free protein synthesis approach with highly sensitive ¹H-detected solid-state NMR. Insertion of lipids chelated with a paramagnetic Gd³⁺ ion allowed to orient the protein with respect to its membrane anchor using PRE. This information allowed to propose a model for the interaction of NS5A with a direct acting antiviral.

RNA aptamers find increasing application in synthetic biology as exogenous gene control elements, but high-resolution structural characterization in vivo is challenging. We report here the NMR-spectroscopic observation of ligand binding by the 2′-deoxyguanosine riboswitch aptamer in eukaryotic cells and show that the binding mode established by in vitro characterization of this aptamer is maintained in eukaryotic cellular environment.

By ¹⁹F-labeling of a Pt^IV prodrug (Pt-FBA, FBA=p-fluorobenzoate), the activation in vitro, in living cells and in mice could be investigated by NMR spectroscopy while avoiding the interference of all background signals and allowing the simultaneous detection of pre- and post-activation species.

Diffusion of amyloid fibrils that contain disordered domains can be captured by pulsed-field-gradient NMR experiments. A new theory is presented that interprets the results of these measurements in terms of fibrils’ translational and rotational motion. Application to Sup35NM fibrils demonstrates the feasibility of diffusion-based sorting in complex amyloidogenic samples.

A combination of charge density measurements, solid-state NMR ¹J_NC couplings, and DFT calculations is presented to characterise the transition from an n–π* interaction to bond formation for a series of model crystalline peri-substituted naphthalenes.

Transient timesweep experiments in continuous flow chemistry in conjunction with online monitoring allow for the recording of a wealth of kinetic data using minimal volumes of reactant at a minimum screening time required. The principle is introduced and discussed on the example of online benchtop NMR monitoring of a radical polymerization.

A ³¹Perfect model: Five small molecules in which ³¹P NMR chemical shift tensors are only weakly affected by intermolecular interactions have been investigated. They represent model systems suitable for determining the reference value of the absolute chemical shielding for any theoretical approximation of interest. This quantity allows to convert experimentally measured chemical shifts into theoretically calculated absolute chemical shieldings and vice versa.

A hyperpolarized ultrafast diffusion exchange spectroscopy method is introduced, which allows highly sensitive and efficient quantification of molecular exchange rates by using low-cost, low-field, single-sided and portable NMR instruments. The method can be used to investigate exchange processes in many fields ranging from intra-extracellular exchange of metabolites to atmospheric surfactant solutions.