Development of nanoemulsion formulation containing kinetin for cosmetic use

Emulsions are the most common vehicles used for skin care products and can be prepared by using different techniques. To prepare emulsions, application of high temperature, high enegy input or using an organic solvent may be necessary. However, high temperature may damage the chemical structure of the active substance. Therefore, in this study, emulsion formulations which do not require application of high temperature or energy input have been investigated. Kinetin which is an essential plant growth factor, is an antiaging and a powerful antioxidant material. The aim of the present study is to formulate an emulsion system which can transport the active substance kinetin to the alive epidermis layer. To get the droplets' size to be suitable for this aim, emulsions emulsions with or without organic solvent were developed. Emulsions' viscosities without ethanol were increased with HPMC K15M for a suitable application on the skin. Kinetin was incorporated into systems at concentration of 0.1 %. The droplets were nanometer sized in the formulations with ethanol, and micrometer sized in the formulations without ethanol. The release kinetics of kinetin from the emulsions fitted Higuchi kinetics. Emulsions containing ethanol exhibited a newtonian behaviour, emulsions without ethanol showed non-newtonian viscosity rheogram. The emulsions without ethanol were found to be stable at room temperature for at least six months and the emulsions with ethanol for four months. Key Words: Nanoemulsions, kinetin, egg lecithin.