FACTORIAL DESIGN BASED OPTIMIZATION AND IN-VITRO – EX-VIVO EVALUATION OF CLOBETASOL LOADED NANO STRUCTURED LIPID CARRIERS

The aim of the present work was to develop and evaluate the potential of nanostructured lipid carriers (NLCs) loaded with Clobetasol-17-propionate (CP) as a new approach for the topical treatment of psoriasis. CP-loaded NLCs were prepared by melt emulsification and ultra-sonication method and optimized using 3³ full factorial designs (Design-Expert software 11.0), by using solid lipid (compritol ATO 888) and liquid lipid (oleic acid) and Tween 80 as a surfactant. Drug loaded NLCs were evaluated for various parameters like particle size, surface charge, polydispersity index, entrapment efficiency, surface morphology, thermal analysis, in-vitro drug release through the skin (Franz diffusion cell), drug deposition study and stability. The optimized formulation has a particle size of 91.2 ± 2.37 nm, the zeta potential of -34.7 ± 1.49 mV, polydispersity index of 0.173 ± 0.035 and entrapment efficiency of 85.4 ± 2.89%. Release study demonstrated prolonged CP release from NLCs following Higuchi release kinetics with r² = 0.9838, while pure CP suspension showed quicker drug release obeying zero-order kinetics with r² value of 0.9904. Skin permeation study of CP loaded SLNs suspension showed prolonged drug release up to 24 h. The maximum ex-vivo drug deposition was obtained after developing the drug into NLCs (51.23 µg/ml) when compared to the pure drug (18.34 µg/ml). The prepared NLCs based formulation has proved to be a promising carrier system for the treatment of psoriasis.