THE INFLUENCE OF DEXTRAN ON THE INTERFACIAL PRESSURE OF ADSORBING LAYERS OF 11S GLOBULIN VICIA-FABA AT THE PLANAR N-DECANE AQUEOUS-SOLUTION INTERFACE

The influence of dextran on the interfacial pressure of adsorbing layers of legumin (11S globulin vicia faba) at the planar n-decane/aqueous solution interface was studied under conditions of thermodynamic compatibility and incompatibility between these biopolymers. The thermodynamic incompatibility of legumin with dextran in the bulk aqueous solution leads to an increase in the interfacial pressure of the adsorbing layers of legumin. This effect may be caused by the excluded volume effect between molecules of the biopolymers in the bulk aqueous solution. Opposite effects are observed under conditions of thermodynamic compatibility between these biopolvmers. In the latter case they may be related to the intensification of thermodynamically favourable interactions of legumin with dextran molecules in the bulk aqueous solution.