Keratin immobilized on silica as a new stationary phase for chromatographic modelling of skin permeation

Abstract

Skin permeability of organic compounds depends on their lipophilicity but can also be affected by compounds interactions with specific skin components. A good chromatographic model of percutaneous penetration determined solely by lipophilicity is provided by the immobilized artificial membrane (IAM) columns. To complete the model a new high-performance liquid chromatographic (HPLC) stationary phase was prepared by physical immobilization of keratin on silica support. The keratin immobilized on silica has properties typical for the reversed-phase materials but it retains specifically acidic solutes. The keratin column can be used to conveniently compare keratolytic properties of xenobiotics. It was demonstrated that retention parameters determined on a keratin column can be combined with the retention parameters determined on the IAM column to predict differences in skin permeability within a class of drugs. It has been postulated that HPLC can model skin permeation thus reducing research time and costs as well as the use of laboratory animals.