Mechanical properties, skin permeation and in vivo evaluations of dexibuprofen-loaded emulsion gel for topical delivery.

The aim of this research was to evaluate the gel properties, skin permeation and in vivo drug efficacy of a novel dexibuprofen-loaded emulsion gel for topical delivery. In this study, the dexibuprofen-loaded emulsion gel and ibuprofen-loaded emulsion gel were prepared with isopropanol, Tween 80, propylene glycol, isopropyl myristate and carbopol. Their mechanical properties such as hardness and adhesiveness were assessed. Moreover, their skin permeation, anti-inflammatory and anti-nociceptive efficacy were evaluated using Franz diffusion cell with the hairless mouse skin, the carrageenan-induced paw oedema test and paw pressure test in rat's hind paws compared with the commercial hydrogel, respectively. The dexibuprofen emulsion gel and ibuprofen emulsion gel provided significantly higher hardness and adhesiveness than the commercial hydrogel. The dexibuprofen emulsion gel enhanced skin permeability by about twofold and 3.5-fold without lag time compared to the ibuprofen emulsion gel and the commercial hydrogel, respectively, suggesting its faster skin permeation. Moreover, the anti-inflammatory efficacy and alleviation in carrageenan-induced inflammation was in the order of dexibuprofen emulsion gel > commercial hydrogel > ibuprofen emulsion gel. The dexibuprofen emulsion gel furnished significantly higher nociceptive thresholds than the ibuprofen emulsion gel and the commercial hydrogel, leading to the most improved anti-nociceptive efficacy. Thus, this dexibuprofen-loaded emulsion gel with good mechanical property, rapid skin permeation and excellent anti-inflammatory and anti-nociceptive efficacy would be a strong candidate for the topical delivery of anti-inflammatory dexibuprofen.