INVESTIGATION BY EVANESCENT WAVES OF THE CHARGE AND CONFORMATION OF AN ADSORBED POLYELECTROLYTE AT THE SILICA AQUEOUS-SOLUTION INTERFACE

A new evanescent wave spectroscopic technique which has the capacity to yield conformational (segment density profile) and charge distribution information for polyelectrolytes adsorbed at the solid/aqueous solution interface is reported. In a first step, to illustrate the capacity of this technique, we demonstrate that evanescent wave spectroscopic data may be used to quantitatively determine both the surface excess and the mean separation distance from the interface of charged and uncharged segments attached to the backbone of a model polyelectrolyte adsorbed at the silica/aqueous solution interface.