Nuclear magnetic resonance diffusion

Hakansson, B., Pons, and Soderman, O. Structure determination of a highly concentrated W/O emulsion using pulsed-field-gradient spin-echo nuclear magnetic resonance diffusion diffractograms, Langmuir, 15, 988,1999. 

Nuclear magnetic resonance diffusivities along a salinity scan (see Chapter 4, Section 8) are shown in Figure 8.17. At low salinities we have an oil-in-water microemulsion, which becomes the middle phase microemulsion, and eventually a water-in-oil microemulsion at large salinities. Note that the surfactant diffusivity of the bicontinuous phase is higher than that of the dispersed phase in both oil-in-water and water-in-oil microemulsions because SDS enters a continuous geometry in the middle phase. Butanol, the cosurfactant, is seen here to prefer the continuous phase. 

NMR Nuclear magnetic resonance [223, 224] Chemical shift of splitting of nuclear spin states in a magnetic field H [225], C [226, 227], N [228], F [229], 2 Xe [230] Other Techniques Chemical state diffusion of adsorbed species... 

Carr H Y and Purcell E M 1954 Effects of diffusion on free precession in nuclear magnetic resonance experiments Rhys. Rev. 94 630-8... 

Ahn C B and Cho Z H 1989 A generalized formulation of diffusion effects in pm resolution nuclear magnetic-resonance imaging Med. Rhys. 16 22-8... 

W. Brown, R. Johnsen, P. Stilbs, B. Lindman. Size and shape of nonionic amphiphile (Ci2Eg) micelles in dilute aqueous solutions as derived from quasielastic and intensity of light scattering, sedimentation and pulsed-field-gradient nuclear magnetic resonance self-diffusion data. J Phys Chem 87 4548-4553, 1983. 

A review is given of the application of Molecular Dynamics (MD) computer simulation to complex molecular systems. Three topics are treated in particular the computation of free energy from simulations, applied to the prediction of the binding constant of an inhibitor to the enzyme dihydrofolate reductase the use of MD simulations in structural refinements based on two-dimensional high-resolution nuclear magnetic resonance data, applied to the lac repressor headpiece the simulation of a hydrated lipid bilayer in atomic detail. The latter shows a rather diffuse structure of the hydrophilic head group layer with considerable local compensation of charge density. 

FIG. 23 Comparison of various one-parameter diffusion models. (Reproduced with permission from Ref. 448, Analysis of Diffusion and Structure in Polyacrylamide Gels by Nuclear Magnetic Resonance, M.S. Thesis, Florida State University, Copyright 1997, Brigita Penke.)... 

Balcom, B Fischer, A Carpenter, T Hall, L, Diffusion in Aqueous Gels. Mutual Diffusion Coefficients Measured by One-Dimensional Nuclear Magnetic Resonance Imaging, Journal of the American Chemical Society 115, 3300, 1993. 

Hadden, DA, Master of Science Thesis, Florida State University, Tallahassee, FL, 1999. Hadden, D Rill, RL McFadden, L Locke, BR, Oligonucleotide and Water Self-Diffusion in Pluronic Triblock Copolymer Gels and Solutions by Pulsed Field Gradient Nuclear Magnetic Resonance, Macromolecules 33, 4235, 2000. 

While the nuclear magnetic resonance (NMR) technique has widely been used to study diffusion processes of normal liquids, solids, or colloidal systems, there are only a few applications to molten salts. The spin echo self-diffusion method with pulsed field gradients was applied to molten salts by Herdlicka et al. "" There is no need to set up or maintain a concentration gradient. 

W. S. Price 1997, (Pulsed-field gradient nuclear magnetic resonance as a tool for studying translational diffusion Part 1. Basic theory), Concepts Magn. Reson. 9, 299-336. 

P. T. Callaghan, K. W. Jolley, R. S. J. Humphrey 1983, (Diffusion of fat and water in cheese as studied by pulsed field gradient nuclear magnetic-resonance), Colloid Interface Sci. 93, 521. 

H.-Y. Lee, M. J. McCarthy, S. R. Dungan 1998, (Experimental characterization of emulsion formation and coalescence by nuclear magnetic resonance restricted diffusion techniques), J. Am. Oil Chem. Soc. 75, 463. 

Several mechanisms are involved in the permeability through Caco-2 cells. In order to obtain a more pure measure of membrane permeability, an experimental method based on ghost erythrocytes (red blood cells which have been emptied of their intracellular content) and diffusion constant measurements using nuclear magnetic resonance (NMR) has been proposed [108]. 

Nuclear magnetic resonance provides means to study molecular dynamics in every state of matter. When going from solid state over liquids to gases, besides mole- cular reorientations, translational diffusion occurs as well. CD4 molecule inserted into a zeolite supercage provides a new specific model system for studies of rotational and translational dynamics by deuteron NMR. 

Other supportive evidence for a specific water-solid interaction is available from thermal studies showing the amount of nonfreezable water [57-59], nuclear magnetic resonance [29,60-66], and diffusion studies [67,68]. The evidence is less clear, however, concerning whether there is distinct binding of water to... 

Retention of a protein or protein activity after 105,000y, 1 hr Chromatography on gel filtration columns with large pore sizes Electron microscopy—however, sample preparation may partially reconstitute membranes Decrease in solution turbidity, which may be detected by a diminution in light scattering or an enhancement in light transmission Diffusion of membrane lipids as assayed by nuclear magnetic resonance and electron spin resonance... 

Price, W.S. 1998a. Pulsed-field gradient nuclear magnetic resonance as a tool for studying translational diffusion. II. Experimental aspects. Basic theory. Concepts in Magn. Reson. 10, 197-237. Price, W.S. 1998b. NMR imaging. In Annual Reports on NMR Spectroscopy (G.A. Webb, ed.), Vol. 34, pp. 140-216. Academic Press, New York. 

R. M. Levy and R. P. Sheridan, Combined effect of restricted rotational diffusion plus jumps on nuclear magnetic resonance and fluorescence probes of aromatic ring motions in proteins, Biophys. J. 41, 217-221 (1983). 

---