Desenvolvimento de carreadores lipídicos nanoestruturados contendo extrato de Centella asiatica (L.) Urban para uso tópico

• Autor(a) principal: Rocha, Priscila Bianca Rodrigues da
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6691
• topic: Carreadores lipídicos nanoestruturados; Centella asiatica; Asiaticosídeo; Penetração cutânea; Nanostructured lipid carriers; Centella asiatica; Asiaticoside; Cutaneous penetration; CIENCIAS DA SAUDE

The extract of Centella asiatica L. Urban (CA) plant has been used both for cosmetic purposes and for the treatment of cutaneous diseases, due to its cicatrizing and antiproliferative activities. The main active component of this plant, asiaticoside (AS), has an important effect on scleroderma (ES), a disease that affects the skin causing its thickening and hardening. These characteristics make difficult the localized topical treatment of ES. Thus, nanostructured lipid carriers (NLC) containing the CA extract were developed and characterized for the topical application of AS. The NLC were produced with a 1: 3 mixture of solid and liquid lipids (stearic acid and oleic acid, respectively), 0.25% sodium taurodeoxycholate and 1% soy lecithin by the microemulsion technique. For formulations with higher amounts of lipid, concentrations of 2 to 4% of the lipid mixture were evaluated. After the development of high lipid particles, different concentrations of CA dry extract (0.926, 1.274 and 1.853%) and glycolic extract (1.282, 2.418 and 3.336%) were added to the formulations. All NLC were characterized for mean diameter, polydispersity index (PdI), zeta potential, encapsulation efficiency (EE%) and drug loading (DL%). In vitro release and permeation studies of the unencapsulated extract (aqueous dispersions and commercial cream) and encapsulated were evaluated using Franz cells. The NLC obtained had a mean size of 130 nm and a uniform size distribution, with a PdI of 0.2, and an encapsulation efficiency of more than 90% for NLC containing dry extract and 40% for NLC developed with glycolic extract. The AS release profile from the developed formulations showed a controlled release, no more than 45% in 48 hours of study. Encapsulation of the dry extract in NLC resulted in an increase in AS retention in the stratum corneum 2-fold compared to the unencapsulated extract in aqueous dispersion, but was similar to the retained amount of AS when the commercial formulation was applied topically. NLC developed with glycolic extract were able to increase the permeation of AS to the deeper layers of the skin, when compared to the carriers containing the CA dry extract and the commercial cream. The results suggest that these systems significantly increase the permeation of AS and, therefore, may present potential benefits for the treatment of cutaneous diseases such as ES.