Nanopartículas lipídicas sólidas (NLS) como sistemas de de liberação de Aciclovir para o tratamento tópico de Herpes simples

Abstract

Acyclovir, a synthetic analogue of 2’- deoxiguanosine, is one of the most effective and selective agents against viruses of the Herpes group. Nevertheless, it has been suggested that the topical therapy with acyclovir has low efficacy due to the lack of penetration of a sufficient amount of drug to the basal epidermis, target site of herpes simplex virus. Solid lipid nanoparticles (SLN) represent an alternative carrier system to traditional colloidal carriers, such as emulsions, lipossomes and polymeric micro- and nanoparticles. Several properties such as adhesion to the stratum corneum, occlusive film formation and increase in hydration as well as in percutaneous penetration of active drugs make this system highly promising for the topical delivery. The aim of the present study was to develop and to characterize acyclovir loaded SLN, as well as to evaluate the potential of this carrier system for topical delivery. Neutral-SLN and negative-SLN, prepared by the microemulsion method, showed average diameters of 285.33 ± 40.22 nm and 220.75 ± 12.84 nm, as well as zeta potentials of 6.68 ± 15.27 mV and -42.02 ± 7.04 mV, respectively. The in vitro percutaneous permeation studies showed a significantly higher amount of ACV, permeated through the pig-ear skin in 24 hours, from negative-SLN than neutral-SLN. Moreover, the skin uptake behavior revealed a significantly higher amount of ACV deposited in stratum corneum and viable epidermis after treating with the negative-SLN. Therefore, it can be concluded from our study that negative-SLN may be a promising carrier for topical delivery of ACV.