I was wondering whether anyone could help me to explain why the chemical shifts in my proton and carbon NMR results do not exactly match with those reported in the literature?The solvent used in my experiment is exactly the same as the one used in the literature of reference (CD3OD), however the frequency applied in my experiment was 500MHz as opposed to 400MHz by the study i am comparing my results with.
For example, in my proton NMR spectra, my results are usually 0.08 to 0.26 ppm higher than that in the literature (e.g: 5.16 x 5.00; 7.51 x 7.25). In the carbon NMR, the results, the variation goes from 0.01 to 3.58 ppm.
I wonder, is that acceptable? can I still mention that my results are in agreement with those reported in the literature?
I have looked everywhere and i couldnt find whether there are variation limits for comparison of NMR data.
THANKSSSSSSSSSSSSSS!!!!
Check if somebody has answered this question on NMRWiki QA forum
Did you find this post helpful? |
Similar Threads
Thread
Thread Starter
Forum
Replies
Last Post
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Publication year: 2012
Source:Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 60</br>
Jakob T. Nielsen, Hamid R. Eghbalnia, Niels Chr. Nielsen</br>
The exquisite sensitivity of chemical shifts as reporters of structural information, and the ability to measure them routinely and accurately, gives great import to formulations that elucidate the structure-chemical-shift relationship. Here we present a new and highly accurate, precise,...
nmrlearner
Journal club
0
03-09-2012 09:16 AM
Low-field one-dimensional and direction-dependent relaxation imaging of bovine articular cartilage
Low-field one-dimensional and direction-dependent relaxation imaging of bovine articular cartilage
Publication year: 2011
Source: Journal of Magnetic Resonance, Available online 10 September 2011</br>
Erik*Rössler, Carlos*Mattea, Ayret*Mollova, Siegfried*Stapf</br>
The structure of articular cartilage is separated into three layers of differently oriented collagen fibers, which is accompanied by a gradient of increasing glycosaminoglycan (GAG) and decreasing water concentration from the top layer towards the bone interface. The combined effect of these structural variations results in...
nmrlearner
Journal club
0
09-12-2011 09:00 PM
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Chemical shift prediction for protein structure calculation and quality assessment using an optimally parameterized force field
Publication year: 2011
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, In Press, Accepted Manuscript, Available online 23 May 2011</br>
Jakob T., Nielsen , Hamid R., Eghbalnia , Niels Chr., Nielsen</br>
The exquisite sensitivity of chemical shifts as reporters of structural information, and the ability to measure them routinely and accurately, gives great import to formulations that elucidate the structure-chemical-shift relationship. Here we...
nmrlearner
Journal club
0
05-24-2011 10:02 PM
[NMR paper] Sequence-dependent correction of random coil NMR chemical shifts.
Sequence-dependent correction of random coil NMR chemical shifts.
Related Articles Sequence-dependent correction of random coil NMR chemical shifts.
J Am Chem Soc. 2001 Apr 4;123(13):2970-8
Authors: Schwarzinger S, Kroon GJ, Foss TR, Chung J, Wright PE, Dyson HJ
Random coil chemical shifts are commonly used to detect secondary structure elements in proteins in chemical shift index calculations. While this technique is very reliable for folded proteins, application to unfolded proteins reveals significant deviations from measured random coil...
nmrlearner
Journal club
0
11-19-2010 08:32 PM
[NMR paper] Backbone motions in a crystalline protein from field-dependent 2H-NMR relaxation and
Backbone motions in a crystalline protein from field-dependent 2H-NMR relaxation and line-shape analysis.
Related Articles Backbone motions in a crystalline protein from field-dependent 2H-NMR relaxation and line-shape analysis.
Biopolymers. 2000 Jan;53(1):9-18
Authors: Mack JW, Usha MG, Long J, Griffin RG, Wittebort RJ
We have used 2H-nmr to study backbone dynamics of the 2H-labeled, slowly exchanging amide sites of fully hydrated, crystalline hen egg white lysozyme. Order parameters are determined from the residual quadrupole coupling and...
nmrlearner
Journal club
0
11-18-2010 09:15 PM
[NMR paper] The NMR solution structure and characterization of pH dependent chemical shifts of th
The NMR solution structure and characterization of pH dependent chemical shifts of the beta-elicitin, cryptogein.
Related Articles The NMR solution structure and characterization of pH dependent chemical shifts of the beta-elicitin, cryptogein.
J Biomol NMR. 1998 Nov;12(4):523-34
Authors: Gooley PR, Keniry MA, Dimitrov RA, Marsh DE, Keizer DW, Gayler KR, Grant BR
The NMR structure of the 98 residue beta-elicitin, cryptogein, which induces a defence response in tobacco, was determined using 15N and 13C/15N labelled protein samples. In aqueous...