Because of the formation of disulfide bridges with mucus glycoproteins, the mucoadhesive properties of polymeric compounds can be significantly improved by the covalent attachment of thiol substructures to them. By the transformation of free thiol groups on such polymers in disulfides with mercaptonicotinamides or mercaptopyridoxins these thiol groups become comparatively more reactive resulting in significantly improved mucoadhesive properties. Furthermore, polymers exhibiting disulfide partial structures with mercaptonicotinamides or mercaptopyridoxins do not need to be protected against oxidation. In addition, they show comparatively higher permeation enhancing properties.
