Formulation and evaluation of safflower oil nanoemulsion for cosmetic applications using sucrose monoester / Nor Suraida Abdul Rahman

Nanoemulsions are a class of emulsions with fine droplet size in the range of 20-500nm. Nanoemulsions are not thermodynamically stable and because of that their characteristics depend on the preparation method. The aim of this study is to investigate the effect of formulation and preparation variables of nanophase gel as pre­ nanoemulsion over nanoemulsion properties. Pre-nanoemulsion gel formulation was first developed by varying sucrose monoester, glycerol/water (8:2) and safflower oil composition to form cubical liquid crystalline system or nanophase gel. Then, an emulsion in mean nanometer droplet size was produced by the mixing of pre­ nanoemulsion gel with distilled water under gentle agitation. The effects of different mechanical energy on mean droplet size and stability of nanoemulsion were then determined with respect to the variation of sucrose monoester and safflower oil composition. Smaller droplet sizes of nanoemulsion were produced using stirrer while bigger droplet sizes were obtained using homogenizer. The main mechanism of this nanoemulsion breakdown using high energy emulsification method might be due to coalescence phenomenon. In addition, destabilization of nanoemulsion in long term process could be attributed to Ostwald ripening.