Macromolecular adsorption

The final proof of the physical reality of our model of macromolecular adsorption was provided by simultaneous independent work, by an entirely different method, at the National Bureau of Standards (27). Stromberg et al., allowed polystyrene fractions, besides other polymers, to become adsorbed on ferrochrome plates and determined the thicknesses of the adsorbed layers... 

R. M. Zimmermann, C. F. Schmidt, and H. E. Gaub, Absolute quantities and equilibrium kinetics of macromolecular adsorption measured by fluorescence photobleaching in total internal reflection, J. Colloid Interface Sci. 139, 268-280 (1990). 

Dickinson, E., and Euston, S. R. (1991a). Computer simulation of macromolecular adsorption. In Food Polymers, Gels and Colloids, Dickinson, E. (Ed.), pp. 557-563. Royal Chem. Soc., London. 

The development of models began in earnest (around 1950) when a growing body of experimental data suggested that macromolecular adsorption could not be described by concepts applied successfully to low molecular weight... 

Theories of macromolecular adsorption predict that film thickness should increase as the square root of the molecular weight (Frisch and Simha, 1957), and this has frequently been verified (Stromberg et al., 1965 Rowland and Eirich, 1966). The sparse data for proteins do not permit conclusions regarding molecular weight dependence of film thickness although the limited results in Table VIII indicate that the capacities do appear to be greater for the larger proteins. 

The study of macromolecular adsorption on thin polymer films should also be feasible. Adsorption isotherms can be obtained on any nonfluorescing polymer that can be deposited in thin-film form on quartz. The only limitation is that the film be nonabsorbing at the excitation wavelength and exhibit minimal fluorescence. Thin films of depth d can be studied if [2ird/X] <0.1 and if the film attenuation index k is less than 0.1 (10). Thin films on quartz substrates can then be characterized by other surface analytical techniques. 

Matthiasson E. (1983), The role of macromolecular adsorption in fouling of ultrafiltration membranes. 

Thus, deviations from the ideal Langmuir isotherm can be caused both by intermolecular interactions, which result in an enthalpy of mixing, and by area differences between molecules, which produce a non-ideal entropy of mixing [18]. For a simple case where the interactions are of the Frumkin type and the partial molar areas of solvent and surfactant are constant the entropic effect of area differences results in typical features of macromolecular adsorption, e.g., a steep initial increase of adsorption ( high affinity adsorption) and a very slow rise once the surface is approximately half filled [18]. 

The present paper focuses on results obtained recently on equilibrium and kinetic properties of macromolecular adsorption, at vairious "model" interfaces. We have worked mainly on polyacrylamide as an example of a flexible, water-soluble polymer, and on albumin and fibrinogen as typical plasma proteins. For a number of... 

Keep in mind that several processes are running simultaneously in the system and that they influence one another. These are processes of enlargement of the particles and macromolecular adsorption on the surface of original and forming particles. For all that, aggregation stability depends on the relationship of the coagulation to adsorption velocity constants. The amount of sole coagulated on a unit area in certain time is calculated by the equation... 

Some of the recent findings on reactive systems with electrokinetic transport have revealed certain interesting propositions, which can be potentially exploited to obtain enhanced rates of biomacromolecular transport and hybridization in microfluidic arrangements. For example. Das and Chakraborty [13], in a recent study, have theoretically estabhshed a novel proposition that the rate of macromolecular adsorption can be augmented with application of transverse electric fields across patterned walls of a microfluidic channel. In their study, an approximate fully developed velocity profile was derived, which was subse-... 

Other important aspects are the liquid drainage between approaching emulsion droplets, droplet deformation, transport of molecules in the bulk, rate of macromolecular adsorption, competition between surfactants, and possible chemical reactions. 

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