Related ArticlesA novel 19F-NMR method for the investigation of the antioxidant capacity of biomolecules and biofluids.
Free Radic Biol Med. 1999 Aug;27(3-4):356-63
Authors: Aime S, Calzoni S, Digilio G, Giraudo S, Fasano M, Maffeo D
A new assay for the measurement of the antioxidant capacity of biomolecules by high resolution 19F-NMR spectroscopy is presented here. This method is based on the use of trifluoroacetanilidic detectors, namely trifluoroacetanilide, N-(4-hydroxyphenyl)-trifluoroacetamide and 2-hydroxy-4-trifluoroacetamidobenzoic acid. Upon hydroxyl radical attack, such fluorinated detectors yield trifluoroacetamide and trifluoroacetic acid that can be quantitatively determined by 19F-NMR spectroscopy. Trifluoroacetamide was found to be a reliable reporter of hydroxyl radical attack on the fluorinated detectors, whereas N-(4-hydroxyphenyl)-trifluoroacetamide was found to be the most sensitive detector amongst the ones considered. Therefore, N-(4-hydroxyphenyl)-trifluoroacetamide has been used in competition experiments to assess the antioxidant capacity of a number of low and high molecular weight antioxidants. The antioxidant capacity of a given compound has been scaled in terms of an adimensional parameter, kF, that represents the ratio between the scavenger abilities of the fluorinated detector and the competitor. kF values obtained for low-molecular-mass compounds fall in the range 0.17 < kF < 1.5 and are in good agreement with second order rate constants (k2OH) for the reaction of the antioxidant with hydroxyl radicals. The kF value for serum albumin is much larger (46.9) than that predicted from the reported k2OH value. This finding supports the view that the protein can very effectively scavenge hydroxyl radicals as well as secondary radicals. Human blood serum showed that its antioxidant capacity is even higher than that shown by aqueous solutions of albumin at physiologic concentration suggesting a further contribution from other macromolecular serum components.
Liouvillians in NMR: the Direct Method Revisited
Liouvillians in NMR: the Direct Method Revisited
Publication year: 2010
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, In Press, Accepted Manuscript, Available online 30 December 2010</br>
Alex D., Bain , Bob, Berno</br>
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[NMR paper] Analysis of a Plasmodium falciparum EBA-175 peptide with high binding capacity to ery
Analysis of a Plasmodium falciparum EBA-175 peptide with high binding capacity to erythrocytes and their analogues using 1H NMR.
Related Articles Analysis of a Plasmodium falciparum EBA-175 peptide with high binding capacity to erythrocytes and their analogues using 1H NMR.
J Struct Biol. 2003 Feb;141(2):115-21
Authors: Cifuentes G, Guzmán F, Alba MP, Salazar LM, Patarroyo ME
A 175-erythrocyte-binding protein (EBA-175) conserved high-activity binding peptide (HABP), called 1783 (nonimmunogenic, nonprotective against Plasmodium falciparum...
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11-24-2010 09:01 PM
physics of the NMR method.
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1/11/2010 8:46:07 AM GMT
physics of the NMR method.
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11-01-2010 08:53 AM
physics of the NMR method.
http://www.cflhd.gov/resources/agm/images/fig164.jpg
cflhd.gov
1/11/2010 8:46:07 AM GMT
physics of the NMR method.
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11-01-2010 08:53 AM
[Question from NMRWiki Q&A forum] saturation transfer method in NMR
saturation transfer method in NMR
What is meant by saturation transfer method in NMR? How it is useful in giving the structure of blue copper proteins like Azurin, Plastocyanin and Stellacyani? What is the need to go for this technique in blue copper proteins?
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08-27-2010 07:58 PM
[NMR paper] Contributions to protein entropy and heat capacity from bond vector motions measured
Contributions to protein entropy and heat capacity from bond vector motions measured by NMR spin relaxation.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Contributions to protein entropy and heat capacity from bond vector motions measured by NMR spin relaxation.
J Mol Biol. 1997 Oct 10;272(5):790-804
Authors: Yang D, Mok YK, Forman-Kay JD, Farrow NA, Kay LE
The backbone dynamics of both folded and unfolded states of staphylococcal nuclease (SNase) and the N-terminal...
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08-22-2010 05:08 PM
[U. of Ottawa NMR Facility Blog] Temperature Calibration - An Alternative Method
Temperature Calibration - An Alternative Method
It is well known that the actual temperature of a sample in an NMR probe is not necessarily the same as that read from the variable temperature unit on the spectrometer. This is because the thermocouple used by the variable temperature unit is below the sample tube and not in the center of the rf coil where the NMR measurements are made. One normally must make a calibration plot for the actual temperature vs. the set temperature. For temperatures above room temperature this can be done by employing the known temperature dependent chemical...
A novel 19F-NMR method for the investigation of the antioxidant capacity of biomolecu
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