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Protein diffusion coefficient measurements by laminar flow analysis: method and applications.

R R Walters·J F Graham·R M Moore·D J Anderson
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Abstract

Laminar flow in an open tube leads to solute band spreading. This process is opposed by radial diffusion. The translational diffusion coefficient of a solute can be calculated from the band dispersion, tube length, and flow rate. No calibration is necessary. A simple apparatus was used to measure the diffusion coefficients of several small solutes and 18 proteins. Most results were within +/- 10% of literature values. Each determination required 7-90 min, depending on the magnitude of the diffusion coefficient. The amount of protein needed was approximately 25 micrograms. The diffusion coefficient data were useful for the estimation of molecular weights.

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Chemical PhenomenaChemistry, PhysicalChromatographyDiffusionMathematicsModels, ChemicalMolecular WeightProteinsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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R R Walters, J F Graham, R M Moore, D J Anderson. 1984. Protein diffusion coefficient measurements by laminar flow analysis: method and applications.. https://doi.org/10.1016/0003-2697(84)90152-0

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