Nanostructured systems containing rutin: in vitro antioxidant activity and photostability studies

• Autor(a) principal: Almeida, Juliana S.
• Data de Publicação: 2010
• Outros Autores: Lima, Fernanda, Ros, Simoní da, Bulhões, Luis O.S., Carvalho, Leandro Machado de, Beck, Ruy Carlos Ruver
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/109964
• topic: Nanocápsulas; Atividade antioxidante; Rutina; Antioxidant activity; Nanocapsules; Nanoemulsions; Nanoparticles; Photostability; Rutin

The improvement of the rutin photostability and its prolonged in vitro antioxidant activity were studied by means of its association with nanostructured aqueous dispersions. Rutin-loaded nanocapsules and rutin-loaded nanoemulsion showed mean particle size of 124.30 ± 2.06 and 124.17 ± 1.79, respectively, polydispersity index below 0.20, negative zeta potential, and encapsulation efficiency close to 100%. The in vitro antioxidant activity was evaluated by the formation of free radical OH after the exposure of hydrogen peroxide to a UV irradiation system. Rutin-loaded nanostructures showed lower rutin decay rates [(6.1 ± 0.6) 10-3 and (5.1 ± 0.4) 10-3 for nanocapsules and nanoemulsion, respectively] compared to the ethanolic solution [(35.0 ± 3.7) 10-3 min-1] and exposed solution [(40.1 ± 1.7) 10-3 min-1] as well as compared to exposed nanostructured dispersions [(19.5 ± 0.5) 10-3 and (26.6 ± 2.6) 10-3, for nanocapsules and nanoemulsion, respectively]. The presence of the polymeric layer in nanocapsules was fundamental to obtain a prolonged antioxidant activity, even if the mathematical modeling of the in vitro release profiles showed high adsorption of rutin to the particle/droplet surface for both formulations. Rutinloaded nanostructures represent alternatives to the development of innovative nanomedicines.