Parahydrogen Polarization in Reverse Micelles and Application to Sensing of Protein-Ligand Binding.

A medium containing reverse micelles supports non-hydrogenative parahydrogen induced polarization (nhPHIP) in the organic phase while solubilizing a protein in the aqueous phase. Strongly enhanced NMR signals from iridium hydride complexes report on a ligand, 4-amino-2-benzylaminopyrimidine, which crosses the phase boundary and interacts with the thiaminase protein TenA. The calculation of binding equilibria reveals a of 39.

Cross-Polarization of Insensitive Nuclei from Water Protons for Detection of Protein-Ligand Binding.

Hyperpolarization derived from water protons enhances the NMR signal of N nuclei in a small molecule, enabling the sensitive detection of a protein-ligand interaction. The water hyperpolarized by dissolution dynamic nuclear polarization (D-DNP) acts as a universal signal enhancement agent. The N signal of benzamidine was increased by 1480-fold through continuous polarization transfer by -coupling-mediated cross-polarization (-CP) via the exchangeable protons.

Measuring Protein-Ligand Binding by Hyperpolarized Ultrafast NMR.

Protein-ligand interactions can be detected by observing changes in the transverse relaxation rates of the ligand upon binding. The ultrafast NMR technique, which correlates the chemical shift with the transverse relaxation rate, allows for the simultaneous acquisition of for carbon spins at different positions. In combination with dissolution dynamic nuclear polarization (D-DNP), where the signal intensity is enhanced by thousands of times, the values of several carbon signals from unlabeled benzylamine are observable within a single scan.

Analysis of Large Data Sets in a Physical Chemistry Laboratory NMR Experiment Using Python.

We describe an update to an experiment demonstrating low-field NMR spectroscopy in the undergraduate physical chemistry laboratory. A Python-based data processing and analysis protocol is developed for this experiment. The Python language is used in fillable worksheets in the notebook software JupyterLab, providing an interactive means for students to work with the measured data step by step.

Relaxometry of SABRE-Hyperpolarized Substrates at a Low Magnetic Field.

Nuclear magnetic resonance (NMR) relaxometry at a low magnetic field, in the milli-Tesla range or less, is enabled by signal enhancements through hyperpolarization. The parahydrogen-based method of signal amplification by reversible exchange (SABRE) provides large signals in a dilute liquid for the measurement of relaxation using a single-scan Carr-Purcell-Meiboom-Gill (CPMG) experiment. A comparison of relaxation rates obtained at high and low fields indicates that an otherwise dominant contribution from chemical exchange is excluded in this low-field range.