Development of curcumin loaded nanostructured lipid carrier based thermosensitive in situ gel for dermal delivery

The objective of this research was to develop novel curcumin-loaded nanostructured lipid carriers (Cur-NLCs) and Cur-NLCs based thermo-sensitive in situ gel (Cur-NLCs-Gel) for topical delivery. Cur-NLCs were prepared using the method of emulsion evaporation-solidification at low temperature and optimized with orthogonal design. The permeation ability of Cur-LNCs and Cur-NLCs-Gel were characterized in vitro. The results showed that the optimized Cur-LNCs represented uniform nano-sized spherical shape with the mean diameter of 263.9 nm. The entrapment efficiency and drug loading were 91.76% and 2.19%, respectively. And there was no significant difference between Cur-NLCs-Gel and Cur-NLCs in morphology, entrapment efficiency and drug loading at the room temperature. The cumulative penetration amount of Cur-NLCs and Cur-NLCs-Gel in vitro were 3,02 times and 2.42 times than that of curcumin propylene glycol solution, respectively. Moreover, in vivo study demonstrated Cur-NLCs-Gel showed the significant anti-inflammatory effect in auricle edemas mice and no obvious irritation to the abdominal skin of rat. Histopathology study of skin showed that Cur-NLCs-Gel could weaken the barrier function of stratum corneum and enhance the permeation of drug into skin. All the evidence showed that NLCs-Gel could provide a promising tuning as a dermal delivery system of curcumin. (C) 2016 Elsevier B.V. All rights reserved.