Multidimensional solution-state NMR

Kaiser, E., Simpson, A. J., Dria, K. J., Sulzberger, B., and Hatcher, P. G. (2003). Solid-state and multidimensional solution-state NMR of solid phase extracted and ultrafiltered riverine dissolved organic matter. Environ. Sci. Technol. 37,2929-2935. 

Simpson, A. (2001). Multidimensional solution state NMR of humic substances A practical guide and review. Soil Sci. 166,795-809. 

In solution-state NMR the tumbling of the individual molecules reduces anisotropic interactions resulting in high-resolution spectra without interference from side bands. Additionally, both proton (this is difficult in solids because strong dipolar interactions produce broad bands) and carbon experiments can be employed to provide quantitative information on NOM mixtures. Furthermore, a range of multidimensional experiments can provide unparalleled information as to the structure... 

There are also multidimensional solid-state NMR experiments, even though, because of the more stringent instrumental requirements, they are more difficult to perform than solution experiments [49-51]. Correlations can be established between the isotropic chemical shift and chemical-shift anisotropy, and between isotropic shift and dipolar coupling. Solid-state exchange NMR provides information about the geometry of molecular motion in the sample, and spin-diffusion measurements are useful for probing domain size [52,53]. 

T. Parella, 2D methods for the measurement of long-range proton-carbon coupling constants, in Multidimensional NMR Methods for the Solution State, G. A. Morris and J. W. Emsley (eds.), John Wiley Sons Ltd, Chichester, 2010, pp. 305-314. 

The development and application of multidimensional solid state homo- and heteronuclear correlation (HETCOR) NMR techniques have lead to an increasingly important role in structure solution of zeolitic materials and have had many practical applications in the detailed structural characterization of completely siliceous zeolites[6,7] and AlPOs.[8-ll] However, HETCOR NMR is not readily applicable to aluminosilicates... 

The work described in this review shows that the organometallic chemistry of the heavier alkali metals has ceased to be an exotic backwater. A good deal of information about the interaction between metal cations and carbanionic fragments has been obtained. Much of it has come from studies on crystalline solids, and although it may be reasonable to expect that the species found in the solid are also present in solution, this has to be established experimentally in each case. Some evidence has been obtained from multinuclear or multidimensional NMR spectroscopy, but so far there have been few studies using solid-state NMR to link structures found in the solid with those in solution. Even when the dominant species in solution is established, still more work is required to determine which species react fastest with particular substrates. The active species in a reaction may be present only in low concentration. 

Initial studies with synthetic PrP peptides focused on the identification of protein domains that could be involved in the conformational conversion of PrP into disease-associated species. To test the hypothesis that this conversion involves the transition of a helices into (3 sheet, Gasset et al (1992) examined the physicochemical properties of peptides homologous to residues 109-122,129-141,178-191, and 202-218 of Syrian hamster PrP, which were predicted to correspond to a-helical regions (designated HI, H2, H3, and H4, respectively) by computational studies. At variance with the theoretical predictions, peptides HI, H3, and H4 exhibited extensive (3-sheet structure in the solid state and in aqueous solution and assembled into fibrils showing ultrastuctural and tinctorial properties of amyloid, as described in detail later. Multidimensional het-eronuclear NMR has revealed that the prediction of the two C-terminal... 

Cheng and English edited ACS symposium series which covers the solution and solid state NMR investigations for dendrimers, cellulose, polyurethane, polyolefins biopolymers, copolymers and so on. Spiess described a historical overview of role of NMR spectroscopy in polymer science. Newmark summarizes the two dimensional and pulsed gradient diffusion NMR experiments and their applications to polymers Shit et al. reviewed the analysis of polymer molecular weight and copolymer composition by NMR. Sasanuma summarized the the analysis of polyethers and polysulfides by NMR and theoretical calcula-tions Ardelean et al described the principle and its applications of diffusion studies by NMR. Roy et al summarized the structural analysis of Novolak resins by multidimensional NMR. Reviews about NMR study of surfactant polymer blends and the structural elucidation of supramocules are published. 

D.A. Snyder, R. Bruschweiler, Multidimensional correlation spectroscopy by covariance NMR, in G. A. Morris, J.W. Emsley (Eds.), Multidimens. NMR Methods in the Solution State, John Wiley Sons Ltd., Chichester, UK, 2010, pp. 97-105... 

The improvements in technology in the last decade allowed NMR spectroscopy to emerge as one of the most important methods for polymer characterization. High resolution solution NMR, solid-state NMR, and the introduction of multidimensional NMR offer more detailed information, at higher resolution and in diverse conditions, on the polymer structure and polymerization mechanisms, chain conformation, and molecular dynamics of the polymers, blends, and multiphase polymer systems. 

Multidimensional spectroscopy plays an essential role in solution state H NMR, by providing correlations through bonds (COSY, TOCSY), through... 

Gal M, Frydman L (2010) Multidimensional NMR methods for the solution state. In Morris GA, Emsley JW (eds) Encyclopedia of magnetic resonance, Chap. 3. Wiley, Chichester, UK... 

New techniques for data analysis and improvements in instrumentation have now made it possible to carry out stmctural and conformational studies of biopolymers including proteins, polysaccharides, and nucleic acids. NMR, which may be done on noncrystalline materials in solution, provides a technique complementary to X-ray diffraction, which requires crystals for analysis. One-dimensional NMR, as described to this point, can offer structural data for smaller molecules. But proteins and other biopolymers with large numbers of protons will yield a very crowded spectrum with many overlapping lines. In multidimensional NMR (2-D, 3-D, 4-D), peaks are spread out through two or more axes to improve resolution. The techniques of correlation spectroscopy (COSY), nuclear Overhausser effect spectroscopy (NOESY), and transverse relaxation-optimized spectroscopy (TROSY) depend on the observation that nonequivalent protons interact with each other. By using multiple-pulse techniques, it is possible to perturb one nucleus and observe the effect on the spin states of other nuclei. The availability of powerful computers and Fourier transform (FT) calculations makes it possible to elucidate structures of proteins up to 40,000 daltons in molecular mass and there is future promise for studies on proteins over 100,000... 

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