Acquisition of pure-phase diffusion spectra using oscillating-gradient spin echo

Momot, Konstantin I.; Kuchel, Philip W.; Chapman, Bogdan E.

doi:10.1016/j.jmr.2005.06.001

Cited by 12 publications

(10 citation statements)

References 21 publications

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“…The estimation of signal is better in the data set that minimizes the t 2 delay time. Although the pulse sequences and algorithm described in this article do not specifically address the problems of homonuclear scalar coupling, it is noted that others have described means to do so (57,58).…”

Section: Discussionmentioning

confidence: 99%

Using PGSE NMR for chemical mixture analysis: Quantitative aspects

Antalek

2007

Concepts Magnetic Resonance

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Pulsed gradient spin echo NMR coupled with a data processing approach such as direct exponential curve resolution algorithm may be used to resolve individual components in a mixture. Differences in the diffusivities of the components lead to differences in their signal decay behavior in the experiment and allow for pure component spectra to be resolved. Because the experiment is echo-based, differences in the relaxation behavior of the nuclei within the various components lead to nonquantitative spectra. As a consequence it is rarely used to directly determine the levels of the components quantitatively. This article explores the effects of signal loss in the PGSE NMR experiment because of relaxation and describes an extrapolation method to ultimately obtain quantitative pure component spectra from mixtures. Examples of surface-modified nanoparticles are presented.

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Section: Discussionmentioning

confidence: 99%

Using PGSE NMR for chemical mixture analysis: Quantitative aspects

Antalek

2007

Concepts Magnetic Resonance

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“…Diffusion experiments were performed using a 10 T m −1 actively shielded diffusion probe (Bruker BioSpin) as described previously fitted with either a 10‐mm 23 Na insert or a 5‐mm 19 F/ 1 H insert. Linear fitting of the signal decay data was performed in Mathematica (Wolfram, Champaign, IL, USA) to estimate the diffusion coefficient.…”

Section: Methodsmentioning

confidence: 99%

Na⁺ and solute diffusion in aqueous channels of Myverol bicontinuous cubic phase: PGSE NMR and computer modelling

Larkin

Garvey

Shishmarev

et al. 2016

Magnetic Reson in Chemistry

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The apparent diffusion coefficients of Na ions and the solute 2-fluoroethylamine present in the aqueous domain of a Myverol/water bulk bicontinuous cubic phase (BCP) were measured using pulsed field-gradient spin echo (PGSE) NMR spectroscopy. The measured values were dependent on the diffusion time interval, which is a characteristic of restricted diffusion. The translational motion of Na and water in the aqueous channels of a cubic phase were simulated using a Monte-Carlo random walk algorithm, and the simulation results were compared with those from real PGSE NMR experiments. The simulations indicated that diffusion of Na ions and water would appear to be restricted even on the shortest timescales available to PGSE NMR experiments. The micro-viscosity of the aqueous domain of the BCPs was estimated from the longitudinal relaxation times of Na and 2-fluoroethylamine; this was three times higher than in free solution and suggests one of (but not the only) likely impediments to the release of hydrophilic drugs from stabilised aqueous dispersions of BCPs (cubosomes) when they are used therapeutically in vivo. Monte Carlo simulations of diffusive efflux from cubosomes suggest that the principal impediment to drug release is presented by a surfactant or lipid barrier at the cubosome surface, which separates the BCP aqueous channels from the bulk solution. The dynamics inferred from these studies informs quantitative predictions of drug delivery from cubosomes. Copyright © 2016 John Wiley & Sons, Ltd.

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“…Takegoshi et al [29] and van Zijl et al [30] reported that a double spin echo with a 90°pulse orthogonal to the first pulse at the time of the first echo can be used to refocus J-evolution for a two-spin system, but that this refocusing is incomplete for higher order spin systems; this approach has been recently implemented for PFG spin echo experiments [31]. The oscillating-gradient spin echo [32] has been used to obtain pure absorption mode spectra for systems with specific coupling constants. Homonuclear decoupling during spin evolution in principle avoids evolution into anti-phase terms [33], but in practice cannot decouple all spins at once.…”

Section: Suppression Of J-modulation Effectsmentioning

confidence: 99%

J-modulation effects in DOSY experiments and their suppression: The Oneshot45 experiment

Botana

Aguilar

Nilsson

et al. 2011

Journal of Magnetic Resonance

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Acquisition of pure-phase diffusion spectra using oscillating-gradient spin echo

Cited by 12 publications

References 21 publications

Using PGSE NMR for chemical mixture analysis: Quantitative aspects

Using PGSE NMR for chemical mixture analysis: Quantitative aspects

Na⁺ and solute diffusion in aqueous channels of Myverol bicontinuous cubic phase: PGSE NMR and computer modelling

J-modulation effects in DOSY experiments and their suppression: The Oneshot45 experiment

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Acquisition of pure-phase diffusion spectra using oscillating-gradient spin echo

Cited by 12 publications

References 21 publications

Using PGSE NMR for chemical mixture analysis: Quantitative aspects

Using PGSE NMR for chemical mixture analysis: Quantitative aspects

Na+ and solute diffusion in aqueous channels of Myverol bicontinuous cubic phase: PGSE NMR and computer modelling

J-modulation effects in DOSY experiments and their suppression: The Oneshot45 experiment

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Na⁺ and solute diffusion in aqueous channels of Myverol bicontinuous cubic phase: PGSE NMR and computer modelling