Development of topical hydrogels containing genistein-loaded nanoemulsions.

This article describes the development of topical hydrogels containing genistein-loaded nanoemulsions, obtained by means of spontaneous emulsification. This procedure yielded monodisperse nanoemulsions in a sub 250 nm range exhibiting negative zeta-potential and low viscosity. The formulations were incorporated into acrylic-acid hydrogels in order to have their viscosity adjusted for topical application.

Validation of an LC method to determine skin retention profile of genistein from nanoemulsions incorporated in hydrogels.

Recent studies have shown the effect of soy isoflavones in preventing skin photoaging and photocarcinogenesis, especially for genistein (GEN). Nanoemulsions have been proposed as a delivery system for GEN administration due to the low water solubility of this isoflavone. This article describes the validation of an isocratic liquid chromatography method to determine GEN in porcine ear skin layers from nanoemulsions before and after incorporation into hydrogels.

A simple and rapid method to assess butenafine hydrochloride in skin samples and a comparative cutaneous retention study of two marketed formulations.

A new method for the quantification of butenafine hydrochloride (BTF) present in the main skin layers was validated and a study conducted with the aim of analyzing the penetration and/or the permeation of the drug. The quantification was performed by liquid chromatography. To evaluate the specificity of the method, the influence of the components of the skin was analyzed, as well as the skin in contact with the excipient ingredients.

Tyrosine promotes oxidative stress in cerebral cortex of young rats.

Tyrosine accumulates in inborn errors of tyrosine catabolism, especially in tyrosinemia type II, where tyrosine levels are highly elevated in tissues and physiological fluids of affected patients. In tyrosinemia type II, high levels of tyrosine are correlated with eyes, skin and central nervous system disturbances. Considering that the mechanisms of brain damage in these disorders are poorly known, in the present study, we investigated whether oxidative stress is elicited by l-tyrosine in cerebral cortex homogenates of 14-day-old Wistar rats.