Diffusion properties of model compounds in artificial sebum.

Sebaceous glands secrete an oily sebum into the hair follicle. Hence, it is necessary to understand the drug partition and diffusion properties in the sebum for the targeted delivery of therapeutic agents into the sebum-filled hair follicle. A new method was developed and used for determination of sebum flux of topical therapeutic agents and other model compounds. The drug transport through artificial sebum was conducted using sebum loaded filter (Transwell) as a membrane, drug suspensions as donor phases and HP-beta-CD buffer solution as a receiver phase. The experiment was performed at 37 degrees C for 2h. The results of the drug transport studies indicate that the flux (J(sebum)) through the artificial sebum is compound dependent and a bell-shaped curve was observed when logJ(s) versus alkyl side chain length of the compounds that proved to be different from the curves obtained upon plotting logJ skin versus clogP for the same compounds, indicating the possibility to select appropriate compounds for sebum targeted delivery based on the differences in the skin flux and sebum transport profiles of the molecules.