Viscosity and diffusion : Crowding and salt effects in protein solutions
(2012) In Soft Matter 8(5). p.1404-1419- Abstract
We report on a joint experimental-theoretical study of collective diffusion in, and static shear viscosity of solutions of bovine serum albumin (BSA) proteins, focusing on the dependence on protein and salt concentration. Data obtained from dynamic light scattering and rheometric measurements are compared to theoretical calculations based on an analytically treatable spheroid model of BSA with isotropic screened Coulomb plus hard-sphere interactions. The only input to the dynamics calculations is the static structure factor obtained from a consistent theoretical fit to a concentration series of small-angle X-ray scattering (SAXS) data. This fit is based on an integral equation scheme that combines high accuracy with low computational... (More)
We report on a joint experimental-theoretical study of collective diffusion in, and static shear viscosity of solutions of bovine serum albumin (BSA) proteins, focusing on the dependence on protein and salt concentration. Data obtained from dynamic light scattering and rheometric measurements are compared to theoretical calculations based on an analytically treatable spheroid model of BSA with isotropic screened Coulomb plus hard-sphere interactions. The only input to the dynamics calculations is the static structure factor obtained from a consistent theoretical fit to a concentration series of small-angle X-ray scattering (SAXS) data. This fit is based on an integral equation scheme that combines high accuracy with low computational cost. All experimentally probed dynamic and static properties are reproduced theoretically with an at least semi-quantitative accuracy. For lower protein concentration and low salinity, both theory and experiment show a maximum in the reduced viscosity, caused by the electrostatic repulsion of proteins. On employing our theoretical and experimental results, the applicability range of a generalized Stokes-Einstein (GSE) relation connecting viscosity, collective diffusion coefficient, and osmotic compressibility, proposed by Kholodenko and Douglas [Phys. Rev. E, 1995, 51, 1081] is examined. Significant violation of the GSE relation is found, both in experimental data and in theoretical models, in concentrated systems at physiological salinity, and under low-salt conditions for arbitrary protein concentrations.
(Less)
- author
- publishing date
- 2012-02-07
- type
- Contribution to journal
- publication status
- published
- in
- Soft Matter
- volume
- 8
- issue
- 5
- pages
- 16 pages
- publisher
- Royal Society of Chemistry
- external identifiers
-
- scopus:84862926002
- ISSN
- 1744-683X
- DOI
- 10.1039/c1sm06242e
- language
- English
- LU publication?
- no
- id
- f436c884-d593-4d65-a91b-578573b0385a
- date added to LUP
- 2018-12-17 09:52:54
- date last changed
- 2022-04-10 04:37:16
@article{f436c884-d593-4d65-a91b-578573b0385a, abstract = {{<p>We report on a joint experimental-theoretical study of collective diffusion in, and static shear viscosity of solutions of bovine serum albumin (BSA) proteins, focusing on the dependence on protein and salt concentration. Data obtained from dynamic light scattering and rheometric measurements are compared to theoretical calculations based on an analytically treatable spheroid model of BSA with isotropic screened Coulomb plus hard-sphere interactions. The only input to the dynamics calculations is the static structure factor obtained from a consistent theoretical fit to a concentration series of small-angle X-ray scattering (SAXS) data. This fit is based on an integral equation scheme that combines high accuracy with low computational cost. All experimentally probed dynamic and static properties are reproduced theoretically with an at least semi-quantitative accuracy. For lower protein concentration and low salinity, both theory and experiment show a maximum in the reduced viscosity, caused by the electrostatic repulsion of proteins. On employing our theoretical and experimental results, the applicability range of a generalized Stokes-Einstein (GSE) relation connecting viscosity, collective diffusion coefficient, and osmotic compressibility, proposed by Kholodenko and Douglas [Phys. Rev. E, 1995, 51, 1081] is examined. Significant violation of the GSE relation is found, both in experimental data and in theoretical models, in concentrated systems at physiological salinity, and under low-salt conditions for arbitrary protein concentrations.</p>}}, author = {{Heinen, Marco and Zanini, Fabio and Roosen-Runge, Felix and Fedunová, Diana and Zhang, Fajun and Hennig, Marcus and Seydel, Tilo and Schweins, Ralf and Sztucki, Michael and Antalík, Marián and Schreiber, Frank and Nägele, Gerhard}}, issn = {{1744-683X}}, language = {{eng}}, month = {{02}}, number = {{5}}, pages = {{1404--1419}}, publisher = {{Royal Society of Chemistry}}, series = {{Soft Matter}}, title = {{Viscosity and diffusion : Crowding and salt effects in protein solutions}}, url = {{http://dx.doi.org/10.1039/c1sm06242e}}, doi = {{10.1039/c1sm06242e}}, volume = {{8}}, year = {{2012}}, }