A relationship between the osmotic second virial coefficient of proteins in aqueous salt solutions, the solubility of proteins in these solutions and the salt concentration is presented. The model developed considers that the solid-liquid equilibrium is established with neutral protein molecules and that the relationship between the protein solubility and the salt concentration follows Cohn's e...

A molecular basis is presented for characterizing the osmotic second virial coefficient, B 22 , of dilute protein solutions, which provides a measure of the nature of protein—protein interactions and has been shown to be correlated with crystallization behavior. Experimental measurements of the second virial coefficient of lysozyme and bovine a-chymotrypsinogen A were performed by static light ...

The volume of the intrafibrillar water space--i.e. the water contained inside the collagen fibres--is a key parameter that is relevant to concepts of connective tissue structure and function. Confined compression and swelling experiments on annulus fibrosus samples are interpreted in terms of a dual porosity model that distinguishes between a non-ionised intrafibrillar porosity and an ionised e...

A weakly charged flexible polyelectrolyte chain in a neutral spherical cavity is analyzed by using self-consistent field theory within an explicit solvent model. Assuming the radial symmetry for the system, it is found that the confinement of the chain leads to creation of a charge density wave along with the development of a potential difference across the center of cavity and the surface. We ...

The effects of ammonium sulphate concentration on the osmotic second virial coefficient (BAA/MA) for equine serum albumin (pH 5.6, 20 degrees C) have been examined by sedimentation equilibrium. After an initial steep decrease with increasing ammonium sulphate concentration, BAA/MA assumes an essentially concentration-independent magnitude of 8-9 ml/g. Such behaviour conforms with the statistica...

The theoretical development for one-dimensional, coupled migration of solutes with different ionic mobilities through clay soils that behave as ion-restrictive membranes, referred to as clay membrane barriers (CMBs), is presented. The transport formulation is based on principles of irreversible thermodynamics and accounts explicitly for coupling effects of hyperfiltration (ultrafiltration) and ...

We have measured the concentration dependence of the osmotic pressure for solutions of core histones in 2.0 M NaC1, pH 8.0, over the concentration range from 1 to 20 mg/ml at 25°C. The ratio of the osmotic pressure to the protein concentration is nearly constant over this range, with a value corresponding to an apparent number average molecular weight of 75,000. Gel filtration of a typical core...

For ternary polymer-salt-water systems at low polymer concentration (0.5%, w/w), we have experimentally investigated the effect of polymer size on polymer diffusiophoresis (i.e., polymer migration induced by a salt concentration gradient) and salt osmotic diffusion (i.e., salt migration induced by a polymer concentration gradient). Specifically, Rayleigh interferometry was employed to measure t...

We present theoretical and numerical studies on stiff, linear polyelectrolytes within the framework of the cell model. We first review analytical results obtained on a mean-field Poisson-Boltzmann level, and then use molecular dynamics simulations to show, under which circumstances these fail quantitatively and qualitatively. For the hexagonally packed nematic phase of the polyelectrolytes we c...

The growth rate and albumin concentration of interstitial fluid cuffs were measured in isolated rabbit lungs inflated with albumin solution (3 g/dl) to constant airway (Paw) and vascular pressures for up to 10 h. Cuff size was measured from images of frozen lung sections, and cuff albumin concentration (Cc) was measured from the fluorescence of Evans blue labeled albumin that entered the cuffs ...