Search

The dynamics of a mixed monolayer consisting of a soluble tailored amphiphile N-decyl-gamma-hydroxybutyric acid amide and its insoluble condensing homologue N-tetradecyl-gamma-hydroxybutyric acid amide are experimentally and theoretically studied. The result reveals that the theoretical predictions are in satisfactory agreement with the experiments.

The thermodynamic and textural properties of dipalmitoyl-phosphatidylglycerol monolayers are described.

The use of bubbles makes it possible to obtain real equilibrium surface tension values of protein solutions. The establishment of equilibrium takes quite a long time.

A model is derived to analyze the cis-trans photoisomerization of a photochromic trifluoromethyl-substituted metacrylate copolymer monolayer. It is shown that the model accurately predicts the characteristics of the components of the cis and trans transformation processes. Among these are that the minimum area demand per repeating unit of the trans conformation is less than that of the cis conformer. Good agreement was also obtained between model and experimental results.

A theoretical and experimental study was conducted that related to research on the use of insoluble-soluble-amphiphile-consisting mixed monolayers to investigate the penetration of insoluble monolayers by a soluble surfactant or protein. The study investigated a simple system consisting of the mixed monolayer of an insoluble, C=20, and soluble, C=12 homologue of dimethylphosphide oxide. It was shown that both the effect of a soluble component on the attributes of the aggregated equilibrium and the effect of the surface pressure increase of the mixed monolayer can be analyzed.

Research was conducted to examine a new equation of state valid for Langmuir monolayers. The theoretical model takes into account the 2D aggregation of monolayer material and the compliance with the important case that the molar area of molecules within an aggregate can differ from that characteristic for free monomers. The Pi-A isotherms for Langmuir monolayers of different amphiphiles are in good agreement with the proposed model for physically reliable values of model parameters.

A study was conducted to analyze the dynamics of surfactant adsorption from solution considering aggregation within the adsorption layer. A multicomponent adsorption layer was assumed to be characterized by monomers and aggregates in equilibrium. Experimental results indicated that the formation of aggregates within the adsorption layer correlated with decreases in the deceleration of the surface tension.

Protein adsorption layers at liquid/fluid interfaces were described using thermodynamic equations derived as a generalization of a novel theory which takes into account the nonideality of enthalpy and entropy of mixing. The effect of the electric charge of the protein molecules on surface pressure was also considered in the proposed theory. Results showed that the derived isotherm is highly consistent with experimental data. The values of the isotherm parameters surface area per molecule, adsorption layer thickness and electric charge of the HSA molecule are approximate to values obtained by other methods in literature.