Skin Permeability Barrier and Drug Permeation

In this project, skin permeation, variations among species and the nature of the skin permeability barrier will be investigated using four different techniques. Skin from animals is very often used in preliminary investigations with dermatological formulations. However, to correlate results with man, we need to understand species variation in permeability characteristics. The techniques are: permeation studies in vitro, differential scanning calorimetry (DSC), thin layer chromatography (TLC) and gas liquid chromatography (GLC). The transdermal permeation of drugs, intended for local and systemic effects, will be investigated. Non-steroidal anti-inflammatory agents, such as ibuprofen and indomethacin, anti-epileptics, such as phenytoin, and antibiotics, such as chloramphenicol, will be selected along with other agents as model drugs. The in vitro permeation studies will be performed using diffusion cells (PermeGear ILC14 Automated System). The amount of drugs penetrating skin will be determined using high performance liquid chromatography technique (HPLC). Data obtained from permeability studies will be analyzed statistically using a specially designed computer software. Factors affecting drug permeation will be studied, to optimize drug release from formulations and the penetration rate across the skin. The effect of species variations on skin permeation of drugs will also be investigated using skin from human and different animal species