Esters of 6-dimethylaminohexanoic acid as skin penetration enhancers

We prepared a series of five esters of 6-dimethylaminohexanoic acid, and ch aracterised the compounds by their NMR and IR spectra. Their ability to fun ction as transdermal penetration enhancers was subsequently evaluated using excised human skin as a membrane, modified Franz diffusion cells, and theo phylline as a model permeant. The penetration enhancing efficiency of ester s 1-5 was studied in the donor media of propylene glycol and isopropyl myri state, and expressed as the corresponding enhancement factors (EF). All the esters increased the penetration of theophylline through the skin. The enh ancement factor for the most active substance, undecyl 6-dimethylaminohexan oate, was 118.5 (+/- 19) from propylene glycol.