Permeation Protection by Waterproofing Mucosal Membranes

The permeability of the oral or nasal mucosa is higher than that of the skin. Mucosa permeability

depends mainly on the thickness and keratinization degree of the tissues. Their permeability

barrier is conditioned by the presence of certain lipids. This work has the main aim of reinforcing the

barrier effect of oral mucosa with a series of formulations to reduce permeation. Transmembrane

water loss of different formulations was evaluated, and three of them were selected to be tested on

the sublingual mucosa permeation of drugs. Caffeine, ibuprofen, dexamethasone, and ivermectin

were applied on porcine skin, mucosa, and modified mucosa in order to compare the effectiveness of

the formulations. A similar permeation profile was obtained in the different membranes: caffeine

> ibuprofen~dexamethasone > ivermectin. The most efficient formulation was a liposomal formulation

composed of lipids that are present in the skin stratum corneum. Impermeability provided

by this formulation was notable mainly for the low-molecular-weight compounds, decreasing their

permeability coefficient by between 40 and 80%. The reinforcement of the barrier function of mucosa

provides a reduction or prevention of the permeation of different actives, which could be extrapolated

to toxic compounds such as viruses, contaminants, toxins, etc.