Mechanistic studies on skin permeation models

• Main Author: Luo, L.
• Published: University College London (University of London) 2017
• Subjects: 615.1
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.746498

The assessment of skin permeation is critically important in many fields and a suitable and robust model that may be used to quantify and predict percutaneous penetration is necessary. Currently available models include in vitro models using human skin, animal skin, synthetic membranes and cell culture models. Recently, the Skin Parallel Artificial Membrane Permeation Assay (PAMPA) has been proposed as a simple but high throughput screening system that may be suitable to study skin permeation. In the present study, a lipophilic active, ibuprofen and a hydrophilic active, caffeine were selected to conduct in vitro permeation studies in the conventional Franz cell models using silicone membrane, porcine skin and human skin, and the novel Skin PAMPA model. The overarching aim was to determine the utility of Skin PAMPA for routine in vitro skin permeation testing with reference to topical formulations. The in vitro permeation studies conducted in Franz cell models using silicone membrane and porcine skin showed that as a lipophilic active, ibuprofen permeated rapidly though silicone membrane and porcine skin. Compared with ibuprofen, caffeine went through the skin more slowly. In vitro permeation studies in Franz cell models using human skin indicated that the ibuprofen percentage permeation values for human skin were much lower than corresponding values in porcine skin as expected. Various in vitro permeation studies were conducted in the novel skin PAMPA model for different ibuprofen and caffeine formulations. In general, the Skin PAMPA model did discriminate between different formulation types and different solvent systems compared with other models, with low variability in the permeation data. The more permeable nature of the PAMPA, silicone membrane and porcine tissue models to ibuprofen compared with human skin was also demonstrated, while the permeation of caffeine, a hydrophilic compound, in the PAMPA model was comparable to that in human skin.