We present a method that enables the direct simulation of Donnan equilibria. The method is based on a grand-canonical Monte Carlo scheme that properly accounts for the unequal partitioning of small ions on the two sides of a semipermeable membrane, and can be used to determine the Donnan electrochemical potential, osmotic pressure, and other system properties. Positive and negative ions are con...

We establish an appropriate thermodynamic framework for determining the optimal genome length in electrostatically driven viral encapsidation. Importantly, our analysis includes the electrostatic potential due to the Donnan equilibrium, which arises from the semipermeable nature of the viral capsid, i.e., permeable to small mobile ions but impermeable to charged macromolecules. Because most mac...

The binding of SCNwith bovine plasma albumin has been studied at 4” by equilibrium dialysis in ethylenediaminetetraacetate and N-(carboxymethyl)-N’,-Z-hydroxyethylN, N’-ethylenediglycine solutions. These two supporting electrolytes were used to minimize Donnan effects. At low ionic strengths (0 to 0.04), the association constants of SCNwere found to increase with decreasing concentrations of su...

Limitations have been detected in a recently published method for macroion valence determination by an ultracentrifugal procedure for quantifying the Donnan distribution of small ions in macroion solutions dialyzed against buffer supplemented with chromate as an indicator ion. The limitation reflects an implicit assumption that sedimentation velocity affords an unequivocal means of separating e...

As manual methods for estimating the concentration of iron in serum are replaced by automated methods it is not always appreciated that the results may not be identical. Babson and Kleinman (1967), in their expei iments with 'serum protein solutions', found that the AutoAnalyzer procedure of Young and Hicks (1965) gave iron results which did not agree with a manual method (Peters, Giovanniello,...

The fluorescence of the dye CC-6 [(3-hexyl-2-(3-hexyl-2-benzoxazolinylidene)-1-propenyl)-benzoxazolium iodide] has been shown to indicate Donnan potentials in rabbit skeletal muscle myofibrils. These results are in agreement with previously published work in which the potentials were measured with microelectrodes on glycerol-extraced muscle fibers. The magnitude of the Donnan potential of the m...

Dear Sir: Gary-Bobo and Solomon (1968, 1971) have employed Gibbs-Donnan equilibrium studies in the assessment o f the anomalous osmotic behavior o f the red cell. In these studies, the interpretation was based on thermodynamic equations for ideal solutions. During the course of recent investigations, we have found that it is necessary to consider the nonideal aspects o f concentrated hemoglobin...