Pravdivtsev, A.N., et al., Exploiting level anti-crossings (LACs) in the rotating frame for transferring spin hyperpolarization. Phys Chem Chem Phys, 2014. 16(35): p. 18707-19.
A method of transferring hyperpolarization among scalar-coupled nuclear spins is proposed, which is based on spin mixing at energy Level Anti-Crossing (LAC) regions. To fulfill LAC conditions a resonant RF-field was applied with properly set frequency and amplitude. In this situation LACs occur between the nuclear spin levels in the rotating doubly tilted reference frame. The validity of the approach is demonstrated by taking as an example the transfer of para-hydrogen induced polarization in a symmetric molecule, whose coupled spin network can be modeled as a four-spin AA'MM'-system with two pairs of 'isochronous' spins. For this spin system LAC positions have been identified; rules for the sign of spin polarization have been established. The dependence of the polarization transfer efficiency on the RF-field parameters and on the time profile of switching off the RF-field has been studied in detail; experimental results are in excellent agreement with the theory developed. In general, exploiting LACs in the rotating doubly tilted frame is a powerful tool for manipulating hyperpolarization in multispin systems.
The role of level anti-crossings in nuclear spin hyperpolarization
From The DNP-NMR Blog:
The role of level anti-crossings in nuclear spin hyperpolarization
Ivanov, K.L., et al., The role of level anti-crossings in nuclear spin hyperpolarization. Prog. NMR. Spec., 2014. 81(0): p. 1-36.
http://www.sciencedirect.com/science/article/pii/S0079656514000454
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Off-resonance rotating-frame relaxation dispersion experiment for 13C in aromatic side chains using L-optimized TROSY-selection
Off-resonance rotating-frame relaxation dispersion experiment for 13C in aromatic side chains using L-optimized TROSY-selection
Abstract
Protein dynamics on the microsecondâ??millisecond time scales often play a critical role in biological function. NMR relaxation dispersion experiments are powerful approaches for investigating biologically relevant dynamics with site-specific resolution, as shown by a growing number of publications on enzyme catalysis, protein folding, ligand binding, and allostery. To date, the majority of studies has probed the...
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Level Anti-Crossings are a Key Factor for Understanding para-Hydrogen-Induced Hyperpolarization in SABRE Experiments
From The DNP-NMR Blog:
Level Anti-Crossings are a Key Factor for Understanding para-Hydrogen-Induced Hyperpolarization in SABRE Experiments
Pravdivtsev, A.N., et al., Level Anti-Crossings are a Key Factor for Understanding para-Hydrogen-Induced Hyperpolarization in SABRE Experiments. ChemPhysChem, 2013. 14(14): p. 3327-3331.
http://www.ncbi.nlm.nih.gov/pubmed/23959909
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04-16-2014 11:09 PM
Level anti-crossings in ParaHydrogen Induced Polarization experiments with Cs-symmetric molecules
From The DNP-NMR Blog:
Level anti-crossings in ParaHydrogen Induced Polarization experiments with Cs-symmetric molecules
Buljubasich, L., et al., Level anti-crossings in ParaHydrogen Induced Polarization experiments with Cs-symmetric molecules. J Magn Reson, 2012. 219(0): p. 33-40.
http://www.ncbi.nlm.nih.gov/pubmed/22595295
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11-21-2013 01:14 AM
Hydration water dynamics in biopolymers from NMR relaxation in the rotating frame.
Hydration water dynamics in biopolymers from NMR relaxation in the rotating frame.
Related Articles Hydration water dynamics in biopolymers from NMR relaxation in the rotating frame.
J Magn Reson. 2010 Sep 24;
Authors: Blicharska B, Peemoeller H, Witek M
Assuming dipole-dipole interaction as the dominant relaxation mechanism of protons of water molecules adsorbed onto macromolecule (biopolymer) surfaces we have been able to model the dependences of relaxation rates on temperature and frequency. For adsorbed water molecules the correlation times are...
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10-22-2010 04:33 PM
[NMR paper] Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and
Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
Related Articles Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
J Magn Reson B. 1994 May;104(1):11-25
Authors: Kuwata K, Brooks D, Yang H, Schleich T
The derivation of a generalized relaxation matrix equation for the off-resonance rotating-frame spin-lattice...
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08-22-2010 03:33 AM
[NMR paper] Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and
Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
Related Articles Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
J Magn Reson B. 1994 May;104(1):11-25
Authors: Kuwata K, Brooks D, Yang H, Schleich T
The derivation of a generalized relaxation matrix equation for the off-resonance rotating-frame spin-lattice...
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08-22-2010 03:33 AM
[NMR paper] Off-resonance rotating frame spin-lattice NMR relaxation studies of phosphorus metabo
Off-resonance rotating frame spin-lattice NMR relaxation studies of phosphorus metabolite rotational diffusion in bovine lens homogenates.
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Biochemistry. 1990 Aug 21;29(33):7547-57
Authors: Caines GH, Schleich T, Morgan CF, Farnsworth PN
The rotational diffusion behavior of phosphorus metabolites present in calf lens cortical and nuclear homogenates was investigated by the NMR technique of...
Exploiting level anti-crossings (LACs) in the rotating frame for transferring spin hyperpolarization
Linear Mode
