Development and evaluation of the effectiveness of bioactive cationic nanoemulsion in protecting hair photo-oxidative damage

Abstract

Products to dye hair fibers are widely used worldwide by the female and also male population, but by different mechanisms, such as washing procedures, and exposure to solar radiation, the hair fiber can present changes in their color characteristics due to oxidation of natural or synthetic pigments present in hair. Solar radiation is one of the responsible for accelerating the process of color change, gloss and protein content reduction of the hair fiber, especially one that was submitted to the coloring process. In order to avoid this problem has been proposed the incorporation of antioxidants in hair care products in order to minimize the harmful effects promoted by oxidative processes and to promote the improvement of the characteristics of the hair fiber, giving characteristics of conditioning as higher tensile strength, brightness, suppleness and elasticity, among others. Nanotechnology has been increasingly used in the development of cosmetic products due to excellent sensory characteristics of the product and increasing efficiency with reduced concentrations of the active components. Another global trend involves the use of substances of plant origin used alone or combined in cosmetic formulations. Therefore, it becomes interesting to incorporate flavonoids of recognized antioxidant activity, for use in hair cationic nanoemulsions, in order to neutralize negative charges present on the fiber due to the isoelectric point of keratin (about 3.8). In this project, the polyphenol quercetin (0.1% w/w) will be incorporated into cationic nanoemulsions, which will be developed by the method of low energy (sub-PIT) and evaluated through the normal stability assessment. The formulations will be applied to tresses of dark brown hair caucasian treated with oxidative dyes in shades blonde or red, which will be exposed to artificial ultraviolet A or B, by a procedure that will be standardized. All tresses will be evaluated for color parameters, tensile rupture and protein loss. (AU)