Characterization of Polymers by GPC-Lalls. I. Computer Simulation of Fractionation of Branched Polymers by GPC

1986 ◽  
Vol 59 (5) ◽  
pp. 693-708 ◽  
Author(s):  
S. Shiga ◽  
E. Kato
Keyword(s):  
Molecular Weight ◽  
Computer Simulation ◽  
Reference Material ◽  
Polymer Structure ◽  
Linear Polymer ◽  
Branched Polymers ◽  
Lower Side ◽  
Elution Volume ◽  
Spreading Function

Abstract Simulation formulae are derived for determining polymer structure in an infinitesimal fraction of GPC elution volume. If a sample is ideally fractionated, the MWD of the momentarily eluted polymer depends chiefly on the DNBP of the injected sample. Statistically branched polymer indicates almost monodisperse MWD at the fraction. Separation is always sharper in the higher molecular weight side of a MWD curve than is in the lower side. Even if the DNBP is broader, the average NBP can be correctly estimated by the method proposed by Kurata et al., as far as the DNBP is nearly Gaussian. When a sample is fractionated by a real GPC with axial dispersion, the MWD of the eluted polymer is mainly controlled by the instrumental spreading function, unless the sample has an extremely wide DNBP or a special MWD. The average NBP by the Kurata et al. equations is expected to be more reliable if a polydisperse linear polymer that yields chromatogram similar to the branched sample is applied as a reference material.

Structural characterization of the capsular polysaccharide and O-chain of the lipopolysaccharide of Actinobacilluspleuropneumoniae serotype 8 (strain 405)

1990 ◽  
Vol 68 (2) ◽  
pp. 329-333 ◽  
Author(s):  
Eleonora Altman ◽  
Jean-Robert Brisson ◽  
Malcolm B. Perry
Keyword(s):  
Molecular Weight ◽  
Nuclear Magnetic Resonance ◽  
High Molecular Weight ◽  
Capsular Polysaccharide ◽  
Teichoic Acid ◽  
Linear Polymer ◽  
Magnetic Resonance Studies ◽  
Acid Type ◽  
Structure Formula

The capsular polysaccharide of Actinobacilluspleuropneumoniae serotype 8 (strain 405) was found to be a teichoic acid type polysaccharide composed of 2-acetamido-2-deoxy-D-galactose (two parts), glycerol (one part), and phosphate (one part). From hydrolysis, dephosphorylation, methylation, and 1H and 13C nuclear magnetic resonance studies, the polysaccharide was found to be a high molecular weight linear polymer having the structure:[Formula: see text]The lipopolysaccharide O-antigen of A. pleuropneumoniae serotype 8 was shown to be a high molecular weight unbranched linear polymer of a repeating pentasaccharide unit having the structure identical to that produced by A. pleuropneumoniae serotype 3, as follows:[Formula: see text]Keywords: Actinobacilluspleuropneumoniae polysaccharide, lipopolysaccharide, NMR.

Developments in column chromatography for the separation and characterization of casein micelles

1979 ◽  
Vol 46 (2) ◽  
pp. 307-311 ◽  
Author(s):  
Thomas C. A. McGann ◽  
Robert D. Kearney ◽  
William J. Donnelly
Keyword(s):  
Molecular Weight ◽  
Skim Milk ◽  
Molecular Size ◽  
Low Molecular Weight ◽  
Elution Profile ◽  
Elution Volume ◽  
Casein Micelles ◽  
Milk Serum ◽  
Molecular Weight Peak

SUMMARYSkim-milk was fractionated by permeation chromatography on CPG-10 (300 nm) at 20 °C with synthetic milk serum. The elution profile, which was highly reproducible, showed 3 partly resolved peaks. On treatment with 0.1% glutaralde-hyde before chromatography, a similar profile was obtained indicating no appreciable micellar dissociation during chromatography of the milk. The casein composition of the eluent fractions, determined by quantitative chromatography on hydroxyapatite, showed that 12.1% of total casein was associated with the low molecular weight peak. The micelle content of ²- and κ-casein increased with increasing elution volume, and the ±s/κ ratio showed a progressive diminution from 4·3 to 2·3. Large differences were found in the colloidal phosphate contents and the weight average diameters of the micelle fractions which clearly show that CPG-10 fractionates on the basis of molecular size.

scholarly journals Synthesis and Characterization of Furans and Levulinates Polymers: Derived from Cellulosic Carbohydrates via Aldol Condensation

2018 ◽  
Vol 53 ◽  
pp. 03011
Author(s):  
Jin Tan ◽  
Chenguang Wang ◽  
Qi Zhang ◽  
Longlong Ma
Keyword(s):  
Molecular Weight ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Aldol Condensation ◽  
Gel Permeation Chromatography ◽  
Polymer Structure ◽  
Synthesis And Characterization ◽  
Key Factors ◽  
Gel Permeation

Aldol condensation between furans and levulinates shows a selective route for the polymers production. In this work, the influences of mole ratio between furans and levulinates as well as substrate species on the formation of polymers structure were investigated. The characterization of gel permeation chromatography and 13C nuclear magnetic resonance to the synthesized polymers suggested that the mole ratio between furans and levulinates, and substrate species exhibited a great effect on the structure of polymers. Higher mole ratios between furans and levulinates resulted in the aggravated polymerization. EMF-EL polymers showed larger molecular weight distribution compared with FFA-EL/LA polymers. This investigation further provides other key factors to the decision of polymer structure.

Isolation and Characterization of Plasminogen Activator from Pig Leucocytes

1974 ◽  
Vol 31 (01) ◽  
pp. 072-085 ◽  
Author(s):  
M Kopitar ◽  
M Stegnar ◽  
B Accetto ◽  
D Lebez
Keyword(s):  
Molecular Weight ◽  
Plasminogen Activator ◽  
Gel Electrophoresis ◽  
Gel Filtration ◽  
Ph Optimum ◽  
Isolation And Characterization ◽  
Ph Range ◽  
Inhibition Studies ◽  
Final Purification

SummaryPlasminogen activator was isolated from disrupted pig leucocytes by the aid of DEAE chromatography, gel filtration on Sephadex G-100 and final purification on CM cellulose, or by preparative gel electrophoresis.Isolated plasminogen activator corresponds No. 3 band of the starting sample of leucocyte cells (that is composed from 10 gel electrophoretic bands).pH optimum was found to be in pH range 8.0–8.5 and the highest pH stability is between pH range 5.0–8.0.Inhibition studies of isolated plasminogen activator were performed with EACA, AMCHA, PAMBA and Trasylol, using Anson and Astrup method. By Astrup method 100% inhibition was found with EACA and Trasylol and 30% with AMCHA. PAMBA gave 60% inhibition already at concentration 10–3 M/ml. Molecular weight of plasminogen activator was determined by gel filtration on Sephadex G-100. The value obtained from 4 different samples was found to be 28000–30500.

Studies on the Characterization of Factor VIII and a Co-factor VIII

1974 ◽  
Vol 31 (02) ◽  
pp. 328-338
Author(s):  
M. M. P Paulssen ◽  
H. L. M. A Vandenbussche-Scheffers ◽  
P. B Spaan ◽  
T de Jong ◽  
M. C Planje
Keyword(s):  
Molecular Weight ◽  
Factor Viii ◽  
The Body ◽  
Haemophilia A ◽  
Von Willebrand's Disease ◽  
Von Willebrand’S Disease ◽  
Polysaccharide Content ◽  
Plasma Factor ◽  
Two Factors

SummaryFactor VIII occurs in the body in two different forms. In lymph factor VIII is bound to chylomicra. In plasma, factor VIII is bound to a protein.After delipidation of chylomicra we obtained a glycoprotein with a high polysaccharide content and a molecular weight of approx. 160,000.In plasma, factor VIII is attached to a protein which is present in normal concentrations in plasma of patients with haemophilia A and in serum (co-factor VIII).This factor is deficient in both the plasma and the serum of patients with von Willebrand’s disease.The binding between factor VIII and co-factor VIII is reversible.Some properties of these two factors are described.

Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

1982 ◽  
Vol 47 (03) ◽  
pp. 197-202 ◽  
Author(s):  
Kurt Huber ◽  
Johannes Kirchheimer ◽  
Bernd R Binder
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Human Urine ◽  
Gel Filtration ◽  
Chain Structure ◽  
The Other ◽  
Single Chain ◽  
Apparent Homogeneity ◽  
Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

Prothrombin Metz : Purification and Characterization of a Variant of Human Prothrombin

1979 ◽  
Author(s):  
M Ribieto ◽  
J Elion ◽  
D Labie ◽  
F Josso
Keyword(s):  
Molecular Weight ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Factor Xa ◽  
Polyacrylamide Gel ◽  
Cleavage Pattern ◽  
Purification And Characterization ◽  
Double Immunodiffusion ◽  
The Family

For the purification of the abnormal prothrombin (Pt Metz), advantage has been taken of the existence in the family of three siblings who, being double heterozygotes for Pt Metz and a hypoprothrombinemia, have no normal Pt. Purification procedures included barium citrate adsorption and chromatography on DEAE Sephadex as for normal Pt. As opposed to some other variants (Pt Barcelona and Madrid), Pt Metz elutes as a single symetrical peak. By SDS polyacrylamide gel electrophoresis, this material is homogeneous and appears to have the same molecular weight as normal Pt. Comigration of normal and abnormal Pt in the absence of SDS, shows a double band suggesting an abnormal charge for the variant. Pt Metz exhibits an identity reaction with the control by double immunodiffusion. Upon activation by factor Xa, Pt Metz can generate amydolytic activity on Bz-Phe-Val-Arg-pNa (S2160), but only a very low clotting activity. Clear abnormalities are observed in the cleavage pattern of Pt Metz when monitored by SDS gel electrophoresis. The main feature are the accumulation of prethrombin l (Pl) and the appearance of abnormal intermediates migrating faster than Pl.

Computer Simulation of Amperometric Biosensor Response to Mixtures of Compounds

2002 ◽  
Vol 7 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
J. Christensen ◽  
F. Ivanauskas ◽  
J. Kulys
Keyword(s):  
Computer Simulation ◽  
Enzymatic Reaction ◽  
Diffusion Equations ◽  
Response Data ◽  
Finite Difference Technique ◽  
Stationary Diffusion ◽  
Biosensor Array ◽  
Menten Kinetic ◽  
Biosensor Response

A mathematical model of amperometric biosensors has been developed. The model bases on non-stationary diffusion equations containing a non-linear term related to Michaelis-Menten kinetic of the enzymatic reaction. The model describes the biosensor response to mixtures of multiple compounds in two regimes of analysis: batch and flow injection. Using computer simulation, large amount of biosensor response data were synthesised for calibration of a biosensor array to be used for characterization of wastewater. The computer simulation was carried out using the finite difference technique.

Removal of Hydrophobic and Hydrophilic Constituents by Anion Exchange Resin

1999 ◽  
Vol 40 (9) ◽  
pp. 207-214 ◽  
Author(s):  
J.-P. Croué ◽  
D. Violleau ◽  
C. Bodaire ◽  
B. Legube
Keyword(s):  
Molecular Weight ◽  
Anion Exchange ◽  
Water Source ◽  
Atomic Ratio ◽  
Size Exclusion ◽  
Salting Out ◽  
Anion Exchange Resins ◽  
Hydrophilic Character ◽  
Exchange Resins

The objective of this work was to compare the affinity of well characterized NOM fractions isolated from two surface waters with strong (gel matrix and macroporous matrix) and weak anion exchange resins (AER) using batch experiment conditions. The structural characterization of the fraction of NOM has shown that the higher the hydrophilic character, the lower the C/O atomic ratio, the lower the SUVA, the lower the aromatic carbon content and the lower the molecular weight. In general (not always), strong AER was more efficient to remove DOC than weak AER. For the same water source (Suwannee River), the higher the molecular weight of the NOM fraction, the lower the affinity with AER. Increasing the ionic strength favored the removal of the hydrophobic NOM fraction (“salting out” effect) while increasing the pH apparently reduced the removal of the hydrophilic NOM fraction. Results were discussed in terms of size exclusion, adsorption, anion exchange and also hydrophobic/hydrophilic repulsion.

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