Disruption of lamellar lipid systems induced by small molecule permeants

Project Description

Current skin penetration models are generally not able to make quantitative predictions across a broad spectrum of compounds. One reason is the difficulty in predicting skin barrier disruption. Improving our ability to quantify the level of disruption caused by a permeant would be a major step forward in making quantitative predictions of skin penetration. P&G is currently putting significant effort into improving the quality of skin penetration models for product safety and efficacy. This is motivated by the fact that many P&G products come into contact with skin including those designed to do so (e.g. lotions, soaps and shampoos) as well as those designed for other purposes but by the nature of their use come into contact with the skin (e.g. cleaning products). Further motivation to develop predictive models for testing products on skin is provided by governmental limitations on animal testing. A ban limiting testing of cosmetics on animals h as been implemented in Europe and will grow more stringent over the next several years. This trend is likely to follow in many other parts of the world. Beyond skin, many lipid systems of industrial importance are present in a non-fluid, gel-like state. In contrast with the typical biologically relevant phospholipid fluid state, this highly ordered phase plays a significant role in many desired properties. When permeants such as dyes and perfumes are added, the phase behavior can be impacted thus causing unwanted or unpredicted behavior. The work proposed here will provide insight into this and is generally applicable to areas beyond skin.