Molar Mass, Radius of Gyration and Second Virial Coefficient from new Static Light Scattering Equations for Dilute Solutions: Application to 21 (Macro)molecules

ChemPhysChem ◽  
2009 ◽  
Vol 10 (7) ◽  
pp. 1097-1105 ◽  
Author(s):  
Bertrand Illien ◽  
Ruifeng Ying
Keyword(s):  
Light Scattering ◽  
Virial Coefficient ◽  
Molar Mass ◽  
Second Virial Coefficient ◽  
Static Light Scattering ◽  
Radius Of Gyration ◽  
Dilute Solutions

scholarly journals Bayesian analysis of static light scattering data for globular proteins

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258429
Author(s):  
Fan Yin ◽  
Domarin Khago ◽  
Rachel W. Martin ◽  
Carter T. Butts
Keyword(s):  
Experimental Data ◽  
Light Scattering ◽  
Virial Coefficient ◽  
Second Virial Coefficient ◽  
Ordinary Least Squares ◽  
Static Light Scattering ◽  
Index Of Refraction ◽  
Scattering Data ◽  
Radius Of Gyration ◽  
Joint Inference

Static light scattering is a popular physical chemistry technique that enables calculation of physical attributes such as the radius of gyration and the second virial coefficient for a macromolecule (e.g., a polymer or a protein) in solution. The second virial coefficient is a physical quantity that characterizes the magnitude and sign of pairwise interactions between particles, and hence is related to aggregation propensity, a property of considerable scientific and practical interest. Estimating the second virial coefficient from experimental data is challenging due both to the degree of precision required and the complexity of the error structure involved. In contrast to conventional approaches based on heuristic ordinary least squares estimates, Bayesian inference for the second virial coefficient allows explicit modeling of error processes, incorporation of prior information, and the ability to directly test competing physical models. Here, we introduce a fully Bayesian model for static light scattering experiments on small-particle systems, with joint inference for concentration, index of refraction, oligomer size, and the second virial coefficient. We apply our proposed model to study the aggregation behavior of hen egg-white lysozyme and human γS-crystallin using in-house experimental data. Based on these observations, we also perform a simulation study on the primary drivers of uncertainty in this family of experiments, showing in particular the potential for improved monitoring and control of concentration to aid inference.

scholarly journals Specific refractive index increments of inulin

2001 ◽  
Vol 66 (6) ◽  
pp. 397-401 ◽  
Author(s):  
Goran Nikolic ◽  
Milorad Cakic ◽  
Ljubomir Ilic
Keyword(s):  
Refractive Index ◽  
Light Scattering ◽  
Approximate Method ◽  
Virial Coefficient ◽  
Molar Mass ◽  
Laser Light ◽  
Second Virial Coefficient ◽  
Laser Light Scattering ◽  
Operating Wavelength ◽  
Differential Refractometer

The specific refractive index increments (dn/dc) of inulin in water, at 25 ?C, were measured at different wavelengths (436, 546 and 589 nm) using a BP-differential refractometer. The dn/dc at the operating wavelength (633 nm) of the laser light scattering photometer was calculated by an approximate method. This value can be used to determine the absolute molar mass and the second virial coefficient of inulin by light scattering photometry.

Light Scattering of Particles Embedded in Soft Hydrogel

1995 ◽  
Vol 60 (10) ◽  
pp. 1719-1727 ◽  
Author(s):  
Minmin Tian ◽  
Zdeněk Tuzar ◽  
Petr Munk
Keyword(s):  
Particle Size ◽  
Light Scattering ◽  
Block Copolymer ◽  
Molar Mass ◽  
Second Virial Coefficient ◽  
Narrow Particle Size Distribution ◽  
Radius Of Gyration ◽  
Structure Information ◽  
Block Copolymer Micelles ◽  
Copolymer Micelles

This study is concerned with soft polyacrylamide gels in which are embedded either polystyrene latexes or block copolymer micelles with polystyrene cores and poly(methacrylic acid) shells. We have found that light scattering provides useful structure information about the systems. For polystyrene latexes, both molar mass and radius of gyration do not change during the embedding in the hydrogel; for block copolymer micelles, molar mass does not change, while the size decreases upon immobilization. In all cases, the second virial coefficient is very small and overshadowed by the turbidity of the sample. For large particles with narrow particle size distribution, a combination of Guinier and Zimm plots has been used for obtaining the particle size and molar mass.

Collapse of Isolated Chains in a Network

1994 ◽  
Vol 376 ◽  
Author(s):  
R. M. Briber ◽  
X. Liu ◽  
B.J. Bauer
Keyword(s):  
Crosslink Density ◽  
Virial Coefficient ◽  
Linear Chain ◽  
Second Virial Coefficient ◽  
Polymer Chains ◽  
Network Density ◽  
Radius Of Gyration ◽  
Single Chain ◽  
Polystyrene Matrix ◽  
Wide Range

ABSTRACTIn this study we use small angle neutron scattering to investigate the conformation of linear deuterated polystyrene chains trapped in a crosslinked protonated polystyrene matrix. The second virial coefficient was obtained as a function of crosslink density for a wide range of crosslink density. It is shown that the second virial coefficient decreases with increasing crosslink density. By extrapolating the scattering to zero concentration of the linear chain at all values of q, the single chain scattering was obtained and radius of gyration was measured the function of network density. It was found that when the network density is low (NI < Nc where NI and Nc are the number of monomer units in the linear chain and the monomer units between crosslinks, respectively) the radius of gyration does not change. As the network density increases (NI > Nc ) radius of gyration decreases. In this region the inverse of the radius of gyration varies linearly with the inverse of Nc. When the crosslink density is very high (NI » Nc ), segregation of linear polymer chains occurs. These results are in agreement with prediction and computer simulation results of polymer chain conformation in a field of random obstacles where the crosslink junctions act as the effective obstacles.

Sign in / Sign up

Export Citation Format

Share Document