The self-diffusion coefficients of different molecular weight PEGs (Polyethylene glycol) and casein particles were measured, using a pulsed-gradient nuclear magnetic resonance technique (PFG-NMR), in native phosphocaseinate (NPC) and sodium caseinate (SC) dispersions where caseins are not structured into micelles. The dependence of the PEG self-diffusion coefficient on the PEG size, casein concentration, the size and the mobility of casein obstacle particles are reported. Wide differences in the PEG diffusion coefficients were found according to the casein particle structure. The greatest reduction in diffusion coefficients was found in sodium caseinate suspensions. Moreover, sodium caseinate aggregates were found to diffuse more slowly than casein micelles for casein concentrations >9*g/100*g H2O. Experimental PEG and casein diffusion findings were analyzed using two appropriate diffusion models: the Rouse model and the Speedy model, respectively. According to the Speedy model, caseins behave as hard spheres below the close packing limit (10*g/100*g H2O for SC (Farrer & Lips, 1999) and 15*g/100*g H2O for NPC (Bouchoux et*al., 2009)) and as soft particles above this limit. Our results provided a consistent picture of the effects of diffusant mass, the dynamics of the host material and of the importance of the casein structure in determining the diffusion behavior of probes in these systems. Graphical abstract
[KPWU blog] change display font/size in Sparky
change display font/size in Sparky
The default font size of Sparky in my 13″ macbook is way big thus I have to move spectrum windows around or move some spectra windows to other desktop. Here is a solution to reduce the font size and the default display sizes of “pointer mode”, “Sparky main window” and individual windows will be smaller http://stats.wordpress.com/b.gif?host=kpwu.wordpress.com&blog=76132&post=703&subd=kpwu&ref=&feed=1
Go to KPWU blog to read complete post.
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04-12-2012 06:12 AM
Impact of (15)N R(2)/R(1) Relaxation Restraints on Molecular Size, Shape, and Bond Vector Orientation for NMR Protein Structure Determination with Sparse Distance Restraints.
Impact of (15)N R(2)/R(1) Relaxation Restraints on Molecular Size, Shape, and Bond Vector Orientation for NMR Protein Structure Determination with Sparse Distance Restraints.
Impact of (15)N R(2)/R(1) Relaxation Restraints on Molecular Size, Shape, and Bond Vector Orientation for NMR Protein Structure Determination with Sparse Distance Restraints.
J Am Chem Soc. 2011 Apr 4;
Authors: Ryabov Y, Schwieters CD, Clore GM
(15)N R(2)/R(1) relaxation data contain information on molecular shape and size as well as on bond vector orientations relative to...
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04-06-2011 10:54 AM
Impact of 15N R2/R1 Relaxation Restraints on Molecular Size, Shape, and Bond Vector Orientation for NMR Protein Structure Determination with Sparse Distance Restraints
Impact of 15N R2/R1 Relaxation Restraints on Molecular Size, Shape, and Bond Vector Orientation for NMR Protein Structure Determination with Sparse Distance Restraints
Yaroslav Ryabov, Charles D. Schwieters and G. Marius Clore
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja201020c/aop/images/medium/ja-2011-01020c_0002.gif
Journal of the American Chemical Society
DOI: 10.1021/ja201020c
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/3J1IyCLkQMQ
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04-05-2011 10:37 AM
[NMR paper] Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed fi
Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed field gradient NMR.
Related Articles Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed field gradient NMR.
Magn Reson Imaging. 2005 Feb;23(2):347-8
Authors: Colsenet R, Soderman O, Mariette F
Molecular transport characterized by diffusion coefficients is a key feature of food processes and especially in dairy processes. Caseins represent 80% of the protein content in milk and are directly involved in the formation of dairy gels....
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11-24-2010 11:14 PM
[NMR paper] Analysis of protein-carbohydrate interaction at the lower size limit of the protein p
Analysis of protein-carbohydrate interaction at the lower size limit of the protein part (15-mer peptide) by NMR spectroscopy, electrospray ionization mass spectrometry, and molecular modeling.
Related Articles Analysis of protein-carbohydrate interaction at the lower size limit of the protein part (15-mer peptide) by NMR spectroscopy, electrospray ionization mass spectrometry, and molecular modeling.
Biochemistry. 2002 Jul 30;41(30):9707-17
Authors: Siebert HC, Lü SY, Frank M, Kramer J, Wechselberger R, Joosten J, André S, Rittenhouse-Olson K, Roy R, von...
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11-24-2010 08:58 PM
[NMR Sparky Yahoo group] Ornament Size
Ornament Size
Hello, I'm having a bit of trouble with the size of the peak ornaments. I'm working with a 4D experment, and although I can adjust the peak ornaments
More...
nmrlearner
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11-12-2010 04:34 AM
[NMR paper] The effects of temperature, viscosity, and molecular size on the aluminum-27 QCT NMR
The effects of temperature, viscosity, and molecular size on the aluminum-27 QCT NMR of transferrins.
Related Articles The effects of temperature, viscosity, and molecular size on the aluminum-27 QCT NMR of transferrins.
J Magn Reson B. 1996 Feb;110(2):182-7
Authors: Aramini JM, Vogel HJ
A number of reports in recent years have demonstrated the feasibility of detecting quadrupolar metal ions bound tightly to rather large proteins via the quadrupolar central transition (QCT) NMR approach. In this article, an in-depth investigation of several...
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08-22-2010 02:27 PM
Lipoprotein size, concentrations associated with incident type 2 diabetes - Endocrine
Lipoprotein size, concentrations associated with incident type 2 diabetes - Endocrine Today
<img alt="" height="1" width="1" />
Lipoprotein size, concentrations associated with incident type 2 diabetes
Endocrine Today
Mora and colleagues used nuclear magnetic resonance spectroscopy on a small blood specimen to measure baseline lipoprotein particle size and concentration, ...
PFG-NMR self-diffusion in casein dispersions: Effects of probe size and protein aggregate size
Linear Mode
