30th IFSCC Congress (International Federation of Societies of Cosmetic Chemists), Munich, 18-21 setembro, 2018.
Renan Lage, Andreia Feital da Costa Pereira, Mamy Honda Igarashi, Sheila Gomes da Silva, Maurizio Mercuri, Elis Angela de Alcantara Viana, Giulia Okamoto Maciente, Amanda Francielli Pereira, Suelma Natalie de Melo Oliveira, Michelle Sabrina Silva, Gustavo Facchini, Ana Lúcia Alves Tabarini Pinheiro, Samara Eberlin.
The skin is a complex system consisting of epidermis, dermis and appendages intertwined between the two layers. The most superficial layer of the skin, the epidermis, is avascular and receives nutrients from the capillaries of the dermis. The corneal layer, considered the outermost of the epidermis, is about 15-20 microns thick and consists of corneocytes (differentiated, anucleated and keratinized keratinocytes) and lipid layers. This morphofunctional structure confers the barrier property of the skin and thus is the stratum corneum which limits permeation of substances. In this sense, cosmetic or pharmaceutical excipients and actives have been researched so that skin barriers are preserved, when the scope of an investigation is safety or diminished, when the goal is permeation. In this study we evaluated the cutaneous permeation of a shampoo and a hair tonic, formulated with a nanoencapsulated active, through fluorescence microscopy using human scalp fragments from elective plastic ritidoplasty. Skin fragments were treated with shampoo and a hair tonic, formulated with a nanoencapsulated active and labeled with Nile Red, for a period of 5 consecutive days. Histological procedures were carried out for posterior evaluation of the skin permeation through the visualization, recording and semi quantification of the fluorescence produced by the nanoencapsulated active labeled with the Red Nile dye. The evaluation of the images obtained revealed a greater intensity of the gray scale emitted by the red channel throughout the histo-anatomical region of hair follicles in the groups treated with both cosmetic formulations shampoo and hair tonic when compared to control and respective placebo formulations. These results were corroborated by the semi-quantification of the fluorescence intensity obtained in the fresh histological sections in the control group and treated with the investigational products. According to the obtained results, we can conclude that the products applied, isolated or associated, on the human scalp demonstrate permeation after 5 days of application throughout the hair follicle area. The association of the products showed a higher intensity of fluorescence when compared to the isolated treatments.
