Test Method for Determination of Weight-Average Molecular Weight of Polymers By Light Scattering

10.1520/d4001 ◽  
2008 ◽  
Author(s):  
Keyword(s):  
Molecular Weight ◽  
Light Scattering ◽  
Average Molecular Weight ◽  
Test Method ◽  
Weight Average Molecular Weight

Fractional Separation and Estimation of Mark-Houwink-Sakurada Equation Parameters for Gluten

2012 ◽  
Vol 8 (1) ◽  
Author(s):  
Lei Zhao ◽  
Lin Li ◽  
Guoqin Liu ◽  
Ling Chen ◽  
Xiaoxi Li ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Liquid Chromatography ◽  
Light Scattering ◽  
Laser Light ◽  
Average Molecular Weight ◽  
Laser Light Scattering ◽  
Size Exclusion ◽  
Gluten Proteins ◽  
Exclusion Chromatography

Fractional separation of gluten using the fast protein liquid chromatography (FPLC) and a numerical method for determination of Mark-Houwink-Sakurada (MHS) equation were studied. With 1% SDS buffer as solvent, the gluten was disassembled into two components: SDS soluble (SDS-S-G) and SDS insoluble gluten proteins (SDS-IS-G). The average molecular weight (Mn, Mw and Mz) and intrinsic viscosity [η] were measured by the multi-angle laser light scattering (MALLS) in conjunction with a size-exclusion chromatography (SEC) and viscosimetry. MHS equations for SDS soluble gluten and SDS insoluble gluten proteins were established as: (SDS-S-G) [η]=1.7459×10-2Mv0.6933=1.7459×10-2qMHSMw0.6933=1.6677×10-2Mw0.6933 (SDS-IS-G) [η]=7.5682×10-3Mv0.7323=7.5682×10-3qMHSMw0.7323=7.2079×10-3Mw0.7323 where qMHS was the polydispersity correction factor.

Size Distribution in the Higher Stages of Polymerization of the A-Protein of Tobacco Mosaic Virus (vulgare)

1979 ◽  
Vol 34 (9-10) ◽  
pp. 782-792 ◽  
Author(s):  
Dieter Vogel ◽  
Guy D. de Marcillac ◽  
Léon Hirth ◽  
Eva Gregori ◽  
Rainer Jaenicke
Keyword(s):  
Molecular Weight ◽  
Light Scattering ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Size Distribution ◽  
Average Molecular Weight ◽  
Spectroscopic Methods ◽  
Weight Average Molecular Weight ◽  
The Third ◽  
Upper Limit

Abstract The composition of the A-protein of tobacco mosaic virus (TMV) has been investigated by se­dimentation velocity, light-scattering, spectroscopic methods, and thermodynamic calculations, at concentrations from 5 to 20 mg/ml, at temperatures from 7 to 26 °C , at various pH and buffer conditions. Above distinct critical concentrations and temperatures aggregates are formed which sediment near 8S, while the concentration of the smaller aggregates that sediment in the trailing boundary, near 4S, remains approximately constant. We identify the 4S protein with two-layer aggregates (Durham and Klug, J. Mol. Biol., 1972), with weight average molecular weight (Mw) near 5 subunits, at the lower limit of polymerization. The 8S aggregates are best described by a series of three-layer aggregates, starting with a heptamer (Caspar, Adv. Protein Chem., 1963), but attaining M̅w corresponding to at least 12 subunits, at the upper limit. The 4S/8S equilibrium is not significantly changed by a change in pH, nor by the coexistence of higher aggregates (20 - 30S) with residual “A-protein”. Three-layer aggregates are more stable than two-layer aggregates, but significantly less stable than would be expected with strictly equivalent bonding; the third lay­er in the 8S protein disturbs the pairing between the two layers in the 4S protein, and the intersub­unit interaction near tryptophan 52 seems to be involved. From the structure, 8S protein should tend to polymerize easier to helices than to disks, in accordance with earlier suggestions (Vogel et al., Eur. J. Biochem., 1977), and corroborated by studies on TMV-mutants.

scholarly journals The Determination of Weight-average Molecular Weight of Hydrophobically Associated Water soluble Polymers

2014 ◽  
Vol 014 (1) ◽  
pp. 150-155
Author(s):  
Feng Ru-sen ◽  
Ji Wei ◽  
Guo Yong-jun ◽  
Sun Jian-hui ◽  
Tang Hao ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Average Molecular Weight ◽  
Water Soluble ◽  
Weight Average Molecular Weight ◽  
Water Soluble Polymers ◽  
Soluble Polymers
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