Liposomal formulations for waterproofing mucosal membranes

Liposome formulations consisting of lipids contained in the stratum corneum have been recently demonstrated to decrease the permeability of mucosae. The permeability barrier of the mucosa is dependent on the presence of specific lipids. The main objective of this work is to reinforce the barrier effect of the oral mucosa with liposomal formulations to decrease permeation. Due to the high similarity in composition and structure between lanolin and human stratum corneum lipids, liposomes were formed with lipids contained in the stratum corneum with two kinds of ceramide or with lanolin. Transmembrane water loss of the two formulations was assessed, obtaining an important diminution for both liposomal formulations. Caffeine, lidocaine, ketoprofen and ivermectin and a virus model were tested on mucosa and on modified mucosa to evaluate the liposomal efficacy. A somewhat consistent permeation pattern was obtained for the different membranes: caffeine > lidocaine > ketoprofen > ivermectin. For all drugs and for the virus model, the most effective formulation was the liposomal formulation, consisting of lipids found in the horny layer of the skin. The effect of the lanolin on the transmembrane water loss is not reflected on the drug permeation. Therefore, it is demonstrated the main role of ceramides in the barrier function for drugs and a virus model. Strengthening the barrier function of the mucosa promotes the prevention or reduction of the permeation of different actives, which could be to extrapolate to harmful actives like viruses, pollutants, toxins, contaminants, etc.