Abstract: The penetration enhancer of nabiletin micromulision gel was optimized and its drug release mechanism in vitro was studied. Orthogonal design was employed to transdermal diffusion test in nasal mucosa of rabbits in vitro, the cumulative permeation quantity and permeation rate of nabiletin were used as indexes to optimize the prescription;Behavior of drug release was studied by modifying diffusion cell and mechanism of drug release was studied by membrane-less model. The results showed that the influence order of different penetration enhancers on cumulative permeation quantity and permeation rate of nabiletin were as follows:azone > borneol > propanediol,while azone had significant influence(P<0.05),and the cumulative release rate of microemulsion gel in 12 hours was 86% which followed the Higuchi equation,erosion rate of microemulsion gel was low and not linearly correlated with the drug release rate(r=0.9387). It was evidently that the prescription of 2% azone,2% borneol and 1% propanediol can be used as the compound penetration enhancer,it had a good property of drug release in vitro and showed controlled release property.

Key words: nobiletin, microemulsion gel, orthogonal test, penetration enhancer