Ogston

W. G. Dukek, A. R. Ogston, and D. R. Winans, Milestones inMviation Fuels, AIAA No. 69—779, American Institute of Aeronautics and Astronautics, New York, July 1969. 

E. Ogston, Antifibrinolytic Drugs Chemistry, Pharmacology and Clinical Usage, ]ohn Wiley Sons, Inc., Chichester, UK, 1984, p. 1. 

Partition coefficients for various gel models are given in Table 3. This table shows the dependence of on the assumed structure of the pores. The Ogston model, for example, gives... 

Johansson and coworkers [182-184] have analyzed polyacrylamide gel structure via several different approaches. They developed an analytical model of the gel structure using a single cylindrical unit cell coupled with a distribution of unit cells. They considered the distribution of unit cells to be of several types, including (1) Ogston distribution, (2) Gaussian distribution of chains, and (3) a fractal network of pores [182-184]. They [183] used the equilibrium partition coefficient... 

Rikvold and Stell [319,320,365] have developed an expression for the partition coefficient in a random two-phase medium made up of spherical particles. They found the partition coefficient to be essentially an exponential function of the solute radius, which is in qualitative agreement with the Ogston theory. 

Many investigators have used the Ogston model and its fundamental idea as a basis for their models. Most recently, Johansson and Elvingson [182] obtained the probability distribution g(r) for spaces in a random suspension of fibers i.e., the probability that a randomly chosen point in a network of fibers is found at a radial distance r to the fiber of closest approach. For a cylindrical cell (CC) model, which consists of an infinite cylindrical cell, containing solvent and polymer, with the polymer represented as a rod centered in the cell, they obtained g(r) for one cylindrical cell as... 

Amsden [14] used the Ogston model coupled with probability argument to find... 

Morris [250] extended the Ogston model to gel electrophoresis. He found empirically that the product of parameters (/v) for gel filtration was proportional to the total monomer con-... 

The standard Rodbard-Ogston-Morris-Killander [326,327] model of electrophoresis which assumes that u alua = D nlDa is obtained only for special circumstances. See also Locke and Trinh [219] for further discussion of this relationship. With low electric fields the effective mobility equals the volume fraction. However, the dispersion coefficient reduces to the effective diffusion coefficient, as determined by Ryan et al. [337], which reduces to the volume fraction at low gel concentration but is not, in general, equal to the porosity for high gel concentrations. If no electrophoresis occurs, i.e., and Mp equal zero, the results reduce to the analysis of Nozad [264]. If the electrophoretic mobility is assumed to be much larger than the diffusion coefficients, the results reduce to that given by Locke and Carbonell [218]. 

Locke, BR Trinh, SH, When Can the Ogston-Morris-Rodbard-Chrambach Model be Applied to Gel Electrophoresis, Electrophoresis 20, 00, 1999. 

Ogston, AG, The Spaces in a Uniform Random Suspension of Fibers, Transactions of the Faraday Society 54, 1754, 1958. 

Ogston, AG Preston, BN Wells, JD, On The Transport of Compact Particles Through Solutions of Chain-Polymers, Proceedings of the Royal Society of London Series A 333, 297, 1973. 

Ogston, AG SUpananta, P, The Thermodynamics of Interaction between Sephadex and Penetrating Solntes, Biochemical Jonmal 116, 171, 1970. 

Slater, GW Guo, HL, Ogston Gel Electrophoretic Sieving How Is the Fractional Volume Available to a Particle Related to Its Mobility and Diffusion Coefficient(s) , Electrophoresis 16,11, 1995. 

Tietz, D, Evaluation of Mobihty Data Obtained from Gel Electrophoresis Shategies in the Computation of Particle and Gel Properties on the Basis of the Extended Ogston Model, Advances in Electrophoresis 2, 109, 1988. 

The combination of Equations (2) and (3) actually predicts a linear relationship between ln(r) and (p. However, according to the Ogston s model, for a homogeneous gel = kkcC, where is the radius of the polymer chain and c is the polymer chain concentration and a linear relationship is expected between ln(r) and c, too. Similarly, the combination of Equations (2) and (4) predicts a linear relationship also between ln(D) and both (p and c. 

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