Annual Reports on NMR Spectroscopy (eBook)

Cover 1
List of Contributors 6
Preface 8
Contents 10
Advances in Probe Design for Protein NMR 12
Introduction 13
Protein NMR Experiments 14
Solution-state pulse sequences 15
Solid-state pulse sequences 17
Pulse sequences for aligned samples 18
Probe Design 18
B1 field homogeneity 19
B0 homogeneity and susceptibility matching 24
Electrical circuit design 28
High frequency models of lumped elements 28
Characteristics of transmission lines 29
Balanced electrical circuits 30
Double-resonant circuits 31
Triple-resonant circuits 32
Cryogenic Probes 34
Theory 34
Practical implementation 36
Multiple frequency operation 38
Effect of buffer properties on cryogenic probe performance 38
Effect of sample geometry on cryogenic probe performance 42
Probe Designs for Minimizing Sample Heating 43
Scroll coils for solid-state MAS 43
Low electric field cross-coil probes for MAS 45
Low electric field probes for aligned samples 47
Solenoidal Coils for Liquid State NMR 48
Single coil probes 48
Multiple-coil probes 52
Conclusions 55
References 56
Diffusion in Soft Polymer Systems as Approached by Field-Gradient NMR 62
Introduction 62
Diffusional Behavior of Probe Molecules in Polymer Networks 63
Diffusion of solvents in polystyrene gels 63
1H PFGSE NMR spectra and their assignments 64
Diffusion coefficient of DMF in network polystyrene gels 66
Diffusion coefficient of THF in network polystyrene gels 67
Effect of the fraction of chloromethylation in the phenyl rings of network polystyrene on the diffusion coefficient of DMF in the gels 69
Diffusion of amino acids in polystyrene gels 70
¹H PFGSE NMR spectra and their assignments 71
Diffusion coefficient of Boc-Gly in network polystyrene gels 73
Diffusion coefficient of Boc-Phe in network polystyrene gels 74
Dependence of the diffusion coefficients of Boc-Phe in network polystyrene gels on the concentration of amino acids 75
Diffusion of regents in polymer supports in for solid-phase synthesis 77
Diffusion coefficients of amino acids in polystyrene network gels with DMF-d7 as solvent 78
Diffusion coefficients of amino acids in polyethylene-glycol-grafted polystyrene network gels and cross-linked ethoxylate acrylate gels with DMF-d7 as solvent 81
Diffusion coefficients of Boc-Phe in polystyrene network gels with THF-d8 as solvent 83
Diffusion coefficients of Boc-PhemiddotCs in network polystyrene gels as a solid-phase reaction field 84
Application of diffusion analysis to solid-phase systems 85
‘‘Required time’’ (Tr) that solvents and amino acids in polymer supports for a solid-phase peptide synthesis diffuse between average diameters of swollen beads 86
Diffusion analysis and inhomogeneity of the network size in polymer gels by time-dependent diffusion NMR 89
Diffusion of solvent in highly oriented PBLG gel with long channel cavities with micrometer-scale diameters 98
Diffusional Behavior of Rod-Like Polymers in the Anisotropic Phase 105
Diffusion of poly(.-n-dodecyl L-glutamate) in the thermotropic liquid crystalline phase 105
Diffusional behavior and dynamics of POLG and POLLG 106
Diffusion of rod-like polypeptides with different main-chain lengths in the thermotropic liquid crystalline state as studied by field-gradient 1H NMR method 111
Analysis of diffusional behavior of rod-like polypeptides 111
Diffusional behavior of PDLGs with different main-chain lengths 113
Diffusion of POLG/CDCl3 in the lyotropic liquid crystalline phase 116
Diffusional behavior of POLG in the isotropic, biphasic and liquid crystalline phases 117
Diffusional behavior of chloroform solvent in highly oriented POLG liquid crystalline solution 122
Diffusion of poly(diethylsiloxane) in the liquid crystalline and isotropic phases 123
Static solid-state 29Si NMR and 1H solid echo NMR spectral analyses 125
Diffusion of PDES in the isotropic phase and in the isotropic region of the biphasic phase 127
Diffusion of n-alkanes in the rotator phase 132
Diffusional behavior of n-alkanes in the rotator phase like the liquid crystalline phase 133
Diffusion of n-alkane in a single crystal at a temperature in the rotator phase 138
Diffusion of n-alkanes in the channels of urea adduct 140
Chain-length dependence of the diffusion coefficients of n-alkanes in urea adduct 141
Diffusing-time dependence of the diffusion coefficients 145
Diffusion of small n-alkanes in the channels of polyester fiber 150
Diffusion of methane in the channels 152
Diffusion of ethane in the channels 157
Conclusions 161
References 161
How Far Can the Sensitivity of NMR Be Increased? 166
Introduction 167
High Magnetic Fields 168
Low Temperature for Stronger Nuclear Spin Polarization 169
NMR at low temperature 169
Parahydrogen-induced polarization 172
Enhancement of Low . Nuclei by Proton Magnetization Transfer 172
Advantages in using magnetization transfer under rf fields 172
Magnetization transfer by NOE 173
Dynamic Nuclear Polarization: Enhancement by Electron Spins 173
Nuclear Polarization Enhancement by Optical Excitation 176
Optical pumping 176
Microwave-induced optical nuclear polarization 177
Photo-CIDNP 178
Detection Schemes to Increase the Sensitivity of NMR 178
Suppression of spin interactions by rf fields and MAS 178
Small rf coils 180
SQUID detection 180
Detection by optical and electrical methods and by atomic beams 180
Magnetic resonance force detection 181
Future Scope 181
References 183
Applications of Low-Field NMR to Food Science 188
Introduction 189
Multidimensional Relaxometry and Diffusometry 190
Multidimensional relaxometry 190
Multidimensional diffusometry 193
Cross-relaxation and diffusive exchange 195
Applications 197
Horticultural products 197
Apple 197
Avocado 200
Pears 202
Peas 202
Potato and starch 203
Meat, egg and fish 204
Dairy products 206
Hydrocolloids 206
Salad cream 206
Cake 206
Relaxometry and Diffusometry in Inhomogeneous Fields 208
Coherent pathway methods 208
Inversion recovery in an inhomogeneous field 209
CPMG sequences in an inhomogeneous field 209
Effective-rotation composite-pulse methods 210
Multidimensional relaxometry and diffusometry in inhomogeneous fields 211
The NMR-MOUSE 211
Open-access Halbach NMR 212
Fast, One-Dimensional Analytical Methods 214
Continuous wave free precession 214
Multiple modulation multiple echoes 215
Single-shot water suppression 216
Single-shot lipid determination by water suppression 216
Single-shot BRIX determination by water suppression 218
Towards High-Resolution Spectroscopy in Inhomogeneous Fields 218
Two-dimensional nutation spectroscopy 218
Shim pulses 220
Z-rotation pulse methods 221
Towards On-line NMR Sensors 221
Motional relativity and radiofrequency excitation 223
Motional relativity and signal acquisition 224
Motional relativity and coil design 225
Prepolarisation 227
Single-shot on-line pulse Sequences 227
Single-shot on-line T² measurements 228
On-line image profiling for foreign body detection 230
Single-shot on-line T1 measurements 230
Single-shot on-line diffusion measurements 230
Single-shot On-line Oil content and BRIX determination 232
Solid Techniques for in-vivo Metabolomics 233
PASS and PHORMAT 233
Field-MAS 234
MRI Studies of Food Processing 235
Cooking 235
Microwave heating of potato 235
Oven grilling of meat 236
Mixing 237
Single-sided MRI 237
Concluding Remarks 238
Acknowledgments 238
References 238
Residual Dipolar Couplings: Measurements and Applications to Biomolecular Studies* 242
Introduction 243
The physical basis of RDC 244
Alignment media 247
The Basic Techniques for Measuring Residual Dipolar Couplings 247
J-resolved experiment 248
Spin-state-selection technique 248
E.COSY method 251
Quantitative J-correlation experiment 252
TROSY experiment 252
General considerations for measurement precision and sensitivity 254
Measurement of Residual Dipolar Couplings in Proteins 255
1H–15N dipolar coupling 256
13Ca–1Ha dipolar coupling 259
Ca--C' dipolar coupling 262
Ca–Cß dipolar coupling 263
N--C' and HN--C' dipolar coupling 264
1H–1H dipolar coupling 266
Experiments for the simultaneous measurement of more than one types of RDCs 267
Measurement of Residual Dipolar Couplings in Nucleic Acids 276
RDC measurement in nucleic acid bases 276
RDC measurements in ribose and backbone of nucleic acids 280
Applications of RDCs to Proteins 281
Automated backbone resonance assignment 281
Assignment requiring an a priori structure 282
Simultaneous assignment and structure determination 284
Structure Determination using RDCs 286
Refinement 287
RDC in combination with other NMR restraints 287
RDC Alone 288
Fold recognition by RDCs 289
Protein folding 293
Alignment media for denatured proteins 293
Native-like topology persistent in the denatured state 293
No native-like topology in the denatured state 294
Protein–ligand interaction 296
Protein–protein interaction 298
Protein– protein orientation by RDCs 298
Protein– protein interface by RDCs in combination with other NMR restraints 300
Conclusions and Future Perspectives 302
Abbreviations 303
Acknowledgments 304
References 305
Index 316