THE INFLUENCE OF THE pH OF THE MEDIUM ON THE SURFACE MORPHOLOGY AND FILM GROWTH DYNAMICS

The research investigated the effect of pH on the surface morphology and film growth. Using the method of layering (LBL) of oppositely charged polyelectrolytes, a coating was obtained on the surface of silicon and glass wafers. Chitosan was used as a polycation, and sodium carboxymethylcellulose plays the role of a polyanion. The choice of both polyelectrolytes is related to their compatibility and biodegradability. The adhesion of the substrate surface was evaluated by an atomic force microscope (AFM). As a result, glass wafers form thin, smooth films due to low adhesion. And also the roughness of different bilayers was investigated and the stages of film formation were shown. The method of ellipsometry was used to determine the dependence of the thickness on the pH of the system. Films collected at pH = 5 are characterized by a lower thickness growth rate compared to films obtained at pH = 3, 4, and 6, since this is due to the conformation of polyelectrolytes. Thus, by controlling the charge density of polyelectrolytes, you can create an antibacterial coating for implantable systems.

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