Brazilian Journal of Pharmaceutical Sciences
On-line version ISSN 2175-9790
GAMBHIRE, Makarand Suresh; BHALEKAR, Mangesh Ramesh and GAMBHIRE, Vaishali Makarand. Statistical optimization of dithranol-loaded solid lipid nanoparticles using factorial design. Braz. J. Pharm. Sci. [online]. 2011, vol.47, n.3, pp.503-511. ISSN 2175-9790. http://dx.doi.org/10.1590/S1984-82502011000300008.
This study describes a 32 full factorial experimental design to optimize the formulation of dithranol (DTH) loaded solid lipid nanoparticles (SLN) by the pre-emulsion ultrasonication method. The variables drug: lipid ratio and sonication time were studied at three levels and arranged in a 32 factorial design to study the influence on the response variables particle size and % entrapment efficiency (%EE). From the statistical analysis of data polynomial equations were generated. The particle size and %EE for the 9 batches (R1 to R9) showed a wide variation of 219-348 nm and 51.33- 71.80 %, respectively. The physical characteristics of DTH-loaded SLN were evaluated using a particle size analyzer, differential scanning calorimetry and X-ray diffraction. The results of the optimized formulation showed an average particle size of 219 nm and entrapment efficiency of 69.88 %. Ex-vivo drug penetration using rat skin showed about a 2-fold increase in localization of DTH in skin as compared to the marketed preparation of DTH.
Keywords : Solid lipid nanoparticles; Homogenization; Ultrasonication; 32 factorial design; Dithranol.