Nuclear magnetic resonance acid gels

MTs = metallothioneins NMR = nuclear magnetic resonance pKa = negative logarithm of acid dissociation constant PMT = photomultiplier tube QITMS = quadrupole ion trap mass spectrometry SBSE = stir bar sorptive extraction SDS-PAGE = sodium dodecylsulfate polyacrylamide gel electrophoresis Se-Cis = selenocystine Se-Cys = selenocysteine Se-Et = selenoethionine Se-Hcy = seleno-homocysteine Se-Met = selenomethionine SEC = supercritical fluid chromatography TBT = tributyltin TETRA = tetramethylarsonium ion Tf = transferrin TMAsO = trimethylarsineoxide TMSe = trimethylselonium ion TOFMS = time of flight mass spectrometry USN = ultrasonic nebulizer. 

Besides amino acid analysis and elaborated mass spectroscopy techniques, many more analytical methods are applied to support the identity examinations of the protein drug, such as determination of the extinction coefficient, isoelectric point, and crystal structure, as well as recording the nuclear magnetic resonance (NMR) and circular dichroism (CD) spectra and determining the chromatographic profiles from HPLC-runs as well as from capillary and polyacrylamide gel electrophoresis (CE and PAGE, respectively). 

Chemical fractionation methods used in this study were gel cFromatography, acid-base neutral solvent partitioning and chromatography on silica gel columns. Identification of compounds was done by gas chromatography/mass spectrometry (GC/MS). Proton nuclear magnetic resonance (PMR) spectroscopy was used to characterize fractions and subfractions which were not amenable to GC/MS analysis. 

Enhanced activity of zeolites with respect to alumina silica gel type of catalysts was ascribed to the enhanced mobility of the protons in the crystalline zeolite bringing about increased acid strength.(73) Thus,though individual catalytic sites may be equivalent, their ensembles of different size would have different catalytic activity.(75) Furthermore C-13 nuclear magnetic resonance of adsorbed molecules showed that strong electric forces present in the regular pores of crystalline zeolites polarize and activate adsorbed molecules (155). 

List of Abbreviations NMR, nuclear magnetic resonance O.D.260> optical density at 260 nm at 25 °C NOESY, nuclear Overhauser effect spectroscopy DQF-COSY, double quantum filtered correlation spectroscopy KP, potassium phosphate Tm, UV-melting point ER, endoplasmic reticulum PAGE, polyacrylamide gel electrophoresis TSP, trisilylpropionic acid sodium salt fid, free induction decay ffh, fifty-four-homologue j57iAf, methionine-rich domain of fifty-four-homologue. 

Extracellular polysaccharides composed of o-glucose, pyruvic acid, and succinic acid have been isolated from a number of strains of Agrobacterium. The conformational behaviour of the extracellular gel-forming polysaccharides from Arthrobacter species has been investigated by nuclear magnetic resonance relaxation and optical rotation techniques. " A number of the polysaccharides studied showed evidence of an ordered conformation which could be melted out on heating. O-Deacetylation destroyed the ordered conformation of two A. viscosus polysaccharides, whilst O-deacylation of the A. stabilis polysaccharide stabilized the ordered structure. 

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