Different BRIJ97 colloid systems as potential enhancers of acyclovir skin permeation and depot.

Graphical abstract Highlights • Different Acyclovir colloidal system based on Brij 97 were prepared and characterized. • Acyclovir percutaneous permeations have been compared with Zovirax® 5%. • All formulations have improved the Acyclovir skin permeation and deposition. • Better results have been obtained with these systems despite drug concentrations lower than Zovirax® 5%. Abstract The low efficacy of Acyclovir topical therapy is due to its physicochemical properties that limit the permeation across the stratum corneum. The goal of this research was to evaluate the ability of biodegradable surfactant, Brij97, to self-assembly in different types of colloid systems which can improve the Acyclovir permeation and accumulation at the target site (the basal epidermis). New Acyclovir formulation based on Brij97 have been analyzed in order to investigate the effect of drug encapsulation on the structure. After that, the in vitro percutaneous permeation of Acyclovir has been compared with that one of the commercial specialty Zovirax® 5%. To estimate the potential of the new formulations proposed as topical delivery, it has been essential to quantify the Acyclovir in the skin layers. The results confirmed that the self-assembly of the surfactant in different nanosized structures improved the amount of permeated Acyclovir and the formation of intracutaneous drug reservoir. Furthermore, the different lipophilicity and structural organization of carriers based on Brij97 showed different influence on the promotion of permeation. The experimental data suggest that the designed carriers could be a valid alternative to improve the efficacy of the current antiviral therapy. [ABSTRACT FROM AUTHOR]