Nanotechnological bioactive hair conditioner to protect hair from ultraviolet radiation

Abstract

Hair treated with oxidative hair dye may, by various mechanisms, including exposure to solar radiation, presents changes in their characteristics of color, brightness and protein content. In order to avoid this problem, it has been proposed to incorporate antioxidants in hair care products in order to minimize oxidative effects and promote the improvement of the characteristics of the hair fiber, like increased tensile strength and elasticity, among others. The Nanotechnology has been increasingly used in the development of cosmetic products due to excellent sensory characteristics of the products and increased efficiency with reduced concentrations of the active components. Another global trend involves the use of bioactive substances used in cosmetic formulations. Therefore, it becomes interesting to incorporate flavonoids recognized by its antioxidant activity, for use in hair cationic nanoemulsions, because the negative charge on the hair 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 developed by sub-PIT method and evaluated through the Normal Stability Assessment. The shape of the micelles will be evaluated by Transmission Electron Microscopy (TEM). The formulations will be applied to Caucasian dark brown hair tresses treated with oxidative blonde or red hair dyes, which will be exposed to artificial ultraviolet A or B radiation. All tresses will be evaluated for color parameters, tensile rupture, protein loss and thermal degradation profile. In this project, we expect to show that nanoemulsions provide greater hair fiber conditioning, compared to macroemulsions prepared with the same composition. The flavonoid quercetin could prevent the oxidation of both artificial pigments present in hair dyes, reducing the color change caused by UV radiation, and the components of the hair fiber, such as proteins, preventing protein loss and improving its mechanical properties. (AU)