RESUMO
We have recently described the incorporation of genistein into topical nanoemulsions. This study describes the physicochemical properties and the genistein permeation profile from these nanoemulsions. Formulations composed of egg lecithin, medium chain triglycerides (MCT) or octyldodecanol (ODD) and water were prepared by spontaneous emulsification. Irrespective of the oil core employed (MCT or ODD), this procedure yielded monodisperse emulsions with mean droplet sizes in the range of 230-280 nm. The addition of genistein in the oil phase, before emulsification, did not alter the properties of nanoemulsions. The amount of genistein incorporated in both formulations was close to 100% (1 mg/mL). Solubility and DSC experiments suggested that egg-lecithin may play an important role on the incorporation of genistein in nanoemulsions. Genistein permeation from formulations was assessed using pig ear skin in Franz type diffusion cells. The overall results showed a slow permeation profile for genistein from both nanoemulsions.Such results open interesting perspectives for the topical administration of genistein.
Assuntos
Genisteína/administração & dosagem , Nanopartículas/química , Administração Tópica , Animais , Varredura Diferencial de Calorimetria , Cultura em Câmaras de Difusão , Eletroquímica , Emulsões , Genisteína/química , Técnicas In Vitro , Indicadores e Reagentes , Microscopia Eletrônica de Transmissão , Óleos , Absorção Cutânea , Solubilidade , SuínosRESUMO
The purpose of this study was to evaluate the toxicity of the oligonucleotide/cationic nanoemulsion complexes on Hep G2 cells through MTT assay. Complexes exhibit droplet size, zeta potential and viscosity of approximately 270 nm, +50mV, and 1.0 cP. Different parameters which may have an influence on toxicity results obtained by MTT assay, i.e. cells number, concentration of MTT reagent and the addition of Soerensen's glycine buffer were first evaluated. In the optimized conditions (1 x 10(4) cells and 0.5 mg/mL MTT), the overall results showed that the addition of increasing amounts of complexes (or nanoemulsions) lead to a progressive toxicity on cells attributed to the presence of the cationic lipid stearylamine in the formulations, whatever the medias's pH is. The IC50 was approximately 200 microg/ml. Such results open interesting perspectives on the use of these nanoemulsions as oligonucleotide delivery systems for Hep G2 cells.
